3D test chart, adjusting arrangement, forming method and adjusting method thereof
11575883 · 2023-02-07
Assignee
Inventors
Cpc classification
International classification
Abstract
A 3D test chart, an adjusting arrangement, a forming method, and an adjusting method thereof are disclosed. The 3D test chart provides a plurality of test patterns arranged at different depths. When testing a photographic arrangement, the photographic arrangement is only required to move for one time or even does not need to be moved, so as to obtain an image containing information of different depths, so that the testing and adjusting process of the photographic arrangement can be easily achieved.
Claims
1. A method of forming a 3D test chart, comprising the steps of: (a) determining at least one predetermined area at each of a plurality of test chart layers; (b) providing at least one test pattern at said predetermined area of each of said plurality of test chart layers; (c) overlapping said plurality of test chart layers in such a manner that said test patterns do not overlap with each other to form said 3D test chart; and (d) configuring at least one light source in such a manner that said light source and a photographic arrangement to be tested are respectively provided at two opposite sides of said 3D test chart, wherein a light beam of said light source passes through said plurality of test chart layers.
2. The method, as recited in claim 1, further comprising a step of projecting light beams to said plurality of test chart layers, wherein a contrast between said test pattern and said corresponding test chart layer is enhanced.
3. The method, as recited in claim 1, wherein said plurality of test chart layers comprises a planar test chart and a focus zooming lens set, and said planar test chart is provided between said light source and said focus zooming lens set in such a manner that said focus zooming lens set and light beams of said light source are able to project information of said planar test chart to form said photographic arrangement to be tested.
4. The method, as recited in claim 3, wherein said planar test chart comprises at least one testing object which is capable of being projected to form said photographic arrangement to be tested by means of said focus zooming lens set, so as to form said test patterns.
5. The method, as recited in claim 1, wherein a shape of said test pattern is selected from the group consisting of a square shape, a triangular shape, a circular shape, an oval shape, a cross shape, a shape of a pair of black and white lines, a star shape, and the combination thereof.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
(31) The following description is disclosed to enable any person skilled in the art to make and use the present invention. Preferred embodiments are provided in the following description only as examples and modifications will be apparent to those skilled in the art. The general principles defined in the following description would be applied to other embodiments, alternatives, modifications, equivalents, and applications without departing from the spirit and scope of the present invention.
(32) The present invention provides a 3D test chart 100 which is arranged for testing a photographic arrangement 10. The photographic arrangement 10 comprises a photographic module 11, an image sensor 12 and other possible components such as a holder. Accordingly, the photographic module 11 and the image sensor 12 are packaged and assembled to form the photographic arrangement 10. When packing the photographic module 11 with the image sensor 12, because the tilt of the image plane of the photographic module 11, as well as the tilt error of other components of the photographic arrangement 10 and the limit of the accuracy of the packaging procedure, it is required to test the focal length of the photographic arrangement 10 and the tilt of the image plane of the photographic module 11 and the image sensor 12, so as to obtain related data for adjusting the relative position of the photographic module 11 and the image sensor 12 based on the data, so that the imaging quality of the photographic arrangement 10 is ensured after the packaging procedure.
(33) Referring to
(34) It is worth mentioning that the parameters of the 3D test chart 100 can be determined according to the type of the photographic arrangement 10, these parameters of the 3D test chart 100 can be the number of the test chart layers 20, the distance between adjacent test chart layers 20, the position of the 3D test chart 100, or the shape, size, position, and the density of each test pattern 21.
(35)
(36) Furthermore, set n as the parameter which represents the number of the layers of the test chart layers 20, set t as the parameter which represents the error tolerance of the photographic arrangement 10 which is predetermined by the manufacturing process, accordingly, the parameter t contains but not limited to error tolerances of the height, the tilt, and the shift of the photographic arrangement 10. In addition, set s as the parameter which represents the number of the moving steps of the photographic arrangement 10. It is worth mentioning that in some examples, the range of the values of the number of the moving steps of the photographic arrangement 10 can be that s>=1. In other words, only one single moving step may be required to move the photographic arrangement 10 for obtaining the corresponding data. Accordingly, the functional equation regarding the number of the layers of the test pattern payers 20 can be as follows: n=f(t,a,s). Thus, the value of the parameter of n can be calculated based on the above formula to calculate the number of the required test chart layers 20. In addition, in other possible examples, the photographic arrangement 10 may not require moving before obtaining the data.
(37) Accordingly, after determining the position of the 3D test chart and the number of the layers of the test chart layers, the shape, position and size of each test pattern 21 can be determined in the following step. According to an example of the present invention, the shape of each test pattern 21 is not limited and may be embodied as a shape selected from the group consisting of a square shape, a triangular shape, a circular shape, an oval shape, a cross shape, a shape of a pair of black and white lines, a star shape and the combination thereof. It is worth mentioning that the shape of each test pattern can be any graph which can be used to calculate the imaging quality of the photographic arrangement 10, including any tangible icons and icons with color difference.
(38) As an example, referring to
(39) Furthermore, referring to
(40) It is worth mentioning that the process for calculating the size L.sub.ij of the test pattern 21 is a procedure for balancing each parameter of the 3D test chart with the error tolerance for manufacturing the 3D test chart 100, and when the size L.sub.ij of the test pattern 21 is determined, the error tolerance for manufacturing the 3D test chart 100 is determined. It is still worth mentioning that when the parameters of the 3D test chart are determined, the 3D test chart can be manufactured based on these parameters.
(41) Accordingly, referring to
(42) (A) Collect the parameters of the photographic arrangement 10 to be tested, and determine the position of the 3D test chart 100.
(43) (B) Determine the number of the layers of the test chart layers of the 3D test chart, and design the layout of the test patterns of the test chart layers according to the precision requirement of the photographic arrangement 10.
(44) More specifically, in the step (A), when the type of the photographic arrangement 10 to be tested is determined, the parameters of the photographic arrangement 10, which including the test field of view, the focal length, and the precision requirement for fitting the back focus, are required to be collected. The person of ordinary skilled in the art should understand that other parameters of the photographic arrangement 10 to be tested can be collected according to different requirements, so that more parameters of the photographic arrangement 10 are obtained to optimize the design of the 3D test chart 100.
(45) Furthermore, in the step (B), the method further comprises a step of determining the size of each test pattern 21.
(46) Preferably, in the step (A), set a as the parameter which represents the precision requirement for fitting the back focus of the photographic arrangement 10 to be tested, set EFL as the parameter which represents the focal length, set h as the parameter which represent the position of the 3D test chart 100, then h.sub.j represents the position of the jth layer of the test chart layers 20, and the functional equation reflecting the position of the test chart layers is as follows: a=−((EFL*(−hj)/(EFL−hj)−(EFL*(−h)/(EFL−h))). Accordingly, based on the above functional equation, the value of h.sub.j can be calculated to determine the position of each test chart layer 20 of the 3D test chart 100.
(47) Preferably, in the step (A), set n as the parameter which represents the number of the layers of the test chart layers 20, set t as the parameter which represents the error tolerance of the photographic arrangement 10 which is predetermined by the manufacturing process, set s as the parameter which represents the number of the moving steps of the photographic arrangement 10, and then obtain the functional equation regarding the number of the layers of the test pattern payers 20 as follows: n=f(t,a,s). In addition, set d as the parameter which represents the layout of the test patterns 21 of the 3D test chart 100, and d.sub.ij is a parameter which represents a distance from a test pattern 21 of a test chart layer 20 to a center of the test chart layer 20, set F as the parameter which represents the testing field of view of the photographic arrangement 10, and obtain the functional equation representing the layout of the test patterns as follows: d.sub.ij=f′(F,h.sub.ij,EFL). Thus, the value of the parameters of n and d.sub.ij can be respectively calculated based on the above formulas to calculate the number of the required test chart layers 20 and the layout of the test patterns 21.
(48) Preferably, set L as the parameter which represents the size of each test pattern 21 and L.sub.ij can be the parameter representing the size of the ith test pattern 21 of the jth test chart layer 20, set t′ as the parameter which represents the error tolerance for manufacturing the 3D test chart 100, set n′ as the parameter which represents the index of refraction of the 3D test chart 100, set s′ as the parameter which represents the allowable disc of confusion during a calculating step of a software, set ΔF as the parameter which represents the allowable range of the span of testing field of view, and then obtain a functional equation regarding the size of the test pattern 21 as follows: L.sub.ij=f″(dij,ΔF,t′,n′,s′). Accordingly, the size of each test pattern 21 can be obtained by calculating the value of L based on the above functional equation.
(49) Accordingly, each test pattern 21 of one of the test chart layers 20 does not overlap with test patterns 21 of other test chart layers 20 along the direction of the depth thereof, so that when the photographic module 11 captures information of each test pattern 21, the test patterns 21 adjacent to the photographic module 11 will not block the light beams reflected or transmitted through the test patterns which are relatively far from the photographic module 11. As an example, according to an embodiment of the present invention, each test pattern 21 of each test chart layer 20 is configured to have an upset trapezoid shape. In other words, the distance from the test pattern 21 to the center of the corresponding test chart layer 20 is gradually decreased from the test patterns 21 far away from the photographic module 11 to the test patterns 21 adjacent to the photographic module 11, as shown in
(50) In other words, the 3D test chart 100 has a plurality of test patterns 21 along the depth thereof which are not overlapping with each other, and two adjacent test patterns 21 are spacedly arranged to form the 3D test chart 100. Accordingly, as an example, each test chart layer 21 is embodied to have a carrier for carrying the test patterns 21. As another example, each test pattern 21 may be formed by a projection method.
(51) Referring to
(52) Preferably, each test chart layer 20 can be made of transparent material, so as to reduce the index of the refraction of each test chart layer 20 as much as possible, and each test pattern 21 of the corresponding test chart layer 20 can be identified and captured by the photographic module 11. In other words, light beams carrying information of one test pattern 21 can pass through other test chart layers 20 without being blocked, so as to be captured by the photographic module 11, so that the photographic arrangement 10 can obtain image of the 3D test chart with information of scenes of different depths.
(53) Referring to
(54)
(55) Accordingly, during the testing process, the light source 40 produces evenly projected light beams which pass through each test chart layer 20 for enhancing the contrast between the test pattern 21 and the corresponding test chart layer 20. It is worth mentioning that all of the light beams passing through the test chart layers with the same performance for enhancing the contrast between the test pattern 21 and the corresponding test chart layer 20, so that when the photographic module 11 receives the light beams, the light beams carrying with the information of the test patterns can be received by the image sensor 12 and then undergo a photoelectric transformation process.
(56) Accordingly,
(57) Furthermore, referring to
(58) Accordingly, the light beams produced by the light sources 40A are evenly projected, and then pass through the test chart layer 20A and produce the contrast between each test pattern 21A and the corresponding test chart layer 20A, so that each test pattern 21A can be easily identified and captured by the photographic module 11.
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(60) It is worth mentioning that the difference between the second embodiment shown in
(61) According to an embodiment of the present invention, each test chart layer 20A may be made of tangible material, or can be formed by a projection method. According to the example shown in
(62) Furthermore, each test pattern 21A can be provided or formed at each carrier layer 30A, so as to form a plurality of test patterns 21A which does not overlap with each other in the direction along the depth thereof. More specifically, as an example, the test pattern 21A can be provided at at least one predetermined area of each carrier layer 30A, and the quantity, size and shape of the predetermined area can be obtained based on the functional equation regarding the test patterns 21A, so that each test pattern 21A is distinguishable from the corresponding carrier layer 30A, so that it is convenient for the photographic module 11 to identify and capture the information of the test patterns 21A.
(63) According to another example of the present invention, the predetermined area of the carrier layer 30A can be selected, and then some chemical or physical treating process is introduced to make the predetermined area distinguishable from other areas, so as to form the test patterns 21A. It is appreciated that other possible method can be employed to form the test patterns 21A at the test chart layers 20A formed by the carrier layers 30A.
(64) Accordingly, as shown in
(65) (a) Determine a predetermined area of a test chart layer 20A, and provide at least one test pattern 21A at the predetermined area.
(66) (b) Overlappedly align a plurality of test chart layers 20A in such a manner that each test pattern 21A of each test chart layer 20A does not overlap with other test patterns 21A of other test chart layers 20A, so as to form the 3D test chart.
(67) Preferably, in the step (b), light beams passing through each test chart layer 20A enhance the contrast between each test pattern 21A and the corresponding test chart layer 20A.
(68) Preferably, in the above method, the 3D test chart 100A may be provided between the light source 40A and the photographic arrangement 10, and light beams of the light sources 40A pass through the test chart layers 20A before reaching to the photographic arrangement 10.
(69) Preferably, in the above method, one or more light sources 40A can be arranged with the photographic arrangement 10 at the same side of the 3D test chart 100A, so that light beams can be reflected by the test patterns 21A.
(70) It is worth mentioning that light beams are evenly distributed to the test chart layers 20A, and it is even worth mentioning that the quantity, size and shape of the predetermine area can be obtained by calculating the functional equation regarding the test patterns 21A.
(71) Referring to
(72) As a detailed example, referring to
(73) Accordingly, the present invention provides a method for forming the 3D test chart 100B, wherein the method comprises a step of providing the projection source 50B in the light path of the light beams of the light source 40B, and forming a plurality of test patterns 21B which do not overlap with each other by the light beams of the light source 40B acting on the projection source 50B. Accordingly, two adjacent test patterns 21B are spacedly arranged with other to from the 3D test chart. Referring to
(74) In this embodiment, when employing the testing device to test the photographic arrangement 10, each test pattern 21B of the 3D test chart 100B is formed in the predetermined space while air may serve as a media, so that the influence of the index of the refraction on the testing result is reduced as much as possible, so as to ensure the testing precision. In addition, the 3D test chart 100B formed by the projection method is still advantageous that the volume of the 3D test chart 100B can be further reduced.
(75)
(76)
(77) As an example, referring to
(78) Furthermore, the projection source 50C comprises a planar test chart 51C and a focus zooming lens set 52C. Accordingly, the planar test chart 51C, which is provided between the light source 40C and the focus zooming lens set 52C, includes at least one test object 511C, so that the light beams of the light sources 40C reach to the test object 511C and form the 3D test chart 100C by means of the focus zooming lens set 52C. It is worth mentioning that the size, position and the quantity of the test object 511C can be adjusted according to different requirements of the 3D test chart 100C.
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(80) Referring to
(81) Furthermore, the cross type test pattern 21D of each test chart layer 20D does not overlap with test patterns 21D of other test chart layers 20D in the direction along the depth thereof, so that when each cross type test pattern 21D is projected to the image space to form an image, they will not interfere with each other in the image, so that the testing precision of the photographic arrangement 10 is ensured because no noise is created when analyzing the imaging resolution of the photographic arrangement based on the image.
(82) Generally speaking, as shown in
(83) As shown in
(84) According to this preferred embodiment of the present invention, in order to prevent the interfering issue and guarantee that the test patterns 21D can occupy as many pixels as possible in the image, the shape of the test pattern 21D can be selected to cross type (i.g. “+”) test pattern 21D or “−” type test pattern 21D when the size of the test pattern is predetermined. In other words, in order to ensure the density of the test patterns in the predetermined areas, the cross type or “−” type test patterns 21D will not interfere with each other when appearing in the image, so that it is possible for the subsequent analyzing step of the imaging resolution of the photographic arrangement 10. In addition, the cross type or “−” type test patterns 21D allows the 3D teat chart to configure more patterns in a limited area, so that the types of the combined patterns can be enriched.
(85) In addition, the cross type or “−” type test patterns 21D can avoid the noise when analyzing the imaging resolution of the photographic arrangement 10 with the 3D test chart. However, it is preferred to configure the test patterns to form shapes both in the meridian and sagittal directions in the image. In other words, when the 3D test chart is employed for analyzing the imaging resolution of the photographic arrangement 10, it is preferred that the projection shapes of the test patterns appear in the image extend along both in meridian and sagittal directions. Since the “−” type test patterns 21D only extend in one direction, it is preferred to choose the cross type test patterns 21D which may extend both in meridian and sagittal directions, so as to meet the testing requirements of the photographic arrangement 10. Therefore, it is possible for configuring more cross type test patterns 21D in a relatively limited area, so that the image formed from shooting the cross type 3D test chart by the photographic arrangement 10 is able to provide more information regarding the imaging resolution of the photographic arrangement 10.
(86) The following disclosure will describe the design and forming method of the cross type 3D test chart, so that the person of ordinary skilled in the art can understand the present invention more clearly. It is appreciate that other details of the embodiment may be technical skills well known in this field and may be omitted in the description of the present invention.
(87) As an example,
(88) In the following description, the process for calculating the size and number of the layers of the cross type test chart layers after measuring the parameters of the photographic arrangement 10 is illustrated in details.
(89) More specifically, set F as the parameter which represents the testing field of view, set EFL as the parameter which represents the focal length of the photographic arrangement 10, and set a as the parameter which represents the precision requirement for fitting the back focus of the photographic arrangement 10. Accordingly, the parameter a reflecting the precision requirement for fitting the back focus is determined by the actual fitting requirement which depends on the processing requirement of the software. Furthermore, set Z as the parameter which represents the testing distance of the cross type 3D test chart 100D, and Z.sub.j represents the testing distance of the jth layer of the test chart layers 20D, the range of the values of j is that j>=2, while Z.sub.1 represents the testing distance of the first layer of the test chart layers 20D which is the test patter layer 20D of the 3D test chart farthest from the photographic module 11, meanwhile, Z.sub.1 is determined when the type of the photographic arrangement 10 is selected. In other words, when the type of the photographic arrangement 10 to be tested is determined, the testing distance of the first layer of the test chart layers 20 is determined at the same time. Furthermore, when the related parameters of the photographic arrangement 10 are obtained, the parameters are used to calculate the position of the cross type 3D test chart and the number of the layers of the test chart layers 20D.
(90) More specifically, set h as the parameter which represent the position of the cross type 3D test chart 100D, then h.sub.j represents the position of the jth layer of the test chart layers 20D, and similarly the range of the values of j is that j>=2, the functional equation reflecting the position of the test chart layers is that a=−((EFL*(−hj)/(EFL−hj)−(EFL*(−h)/(EFL−h))).
(91) Accordingly, based on the above functional equation, the value of h.sub.j can be calculated to determine the position of each test chart layer 20D of the 3D test chart 100D.
(92) Furthermore, set n as the parameter which represents the number of the layers of the test chart layers 20D, set t as the parameter which represents the error tolerance of the photographic arrangement 10 which is predetermined by the manufacturing process, accordingly, the parameter t contains but not limited to error tolerances of the height, the tilt, and the shift of the photographic arrangement 10. In addition, set s as the parameter which represents the number of the moving steps of the photographic arrangement 10. It is worth mentioning that in some examples, the range of the values of the number of the moving steps of the photographic arrangement 10 can be that s>=1. In other words, only one single moving step may be required to move the photographic arrangement 10 for obtaining the corresponding data. Accordingly, the functional equation regarding the number of the layers of the test pattern payers 20D can be as follows: n=f(t,a,s). Thus, the value of the parameter of n can be calculated based on the above formula to calculate the number of the required test chart layers 20D. In addition, in other possible examples, the photographic arrangement 10 may not require moving before obtaining the data.
(93) Accordingly, after determining the position of the cross type 3D test chart and the number of the layers of the test chart layers, the shape, position and size of each test pattern 21D can be determined in the following step
(94) As an example, referring to
(95) Furthermore, referring to
(96) It is worth mentioning that the process for calculating the size L.sub.ij of the cross type test pattern 21D is a procedure for balancing each parameter of the cross type 3D test chart with the error tolerance for manufacturing the cross type 3D test chart 100, and when the size L.sub.ij of the cross type test pattern 21D is determined, the error tolerance for manufacturing the cross type 3D test chart 100D is determined. It is still worth mentioning that when the parameters of the cross type 3D test chart are determined, the cross type 3D test chart can be manufactured based on these parameters.
(97) It is still worth mentioning that since the types of the photographic arrangements 10 can be different, the focal length, the bore diameter, the area range of the image, the size of the imaging unit of the image sensor 12 of different types of the photographic arrangement 10 are varied from each other. In addition, the precision requirement for testing the photographic arrangement 10 as well as the distance from the cross type 3D test chart to the photographic arrangement 10 is considered to calculate the parameters of the cross type 3D test chart.
(98) Furthermore, according to an embodiment of the present invention, the size of the shape of each cross type test pattern 21D in the image should be the same. For example, when the shape of each cross type test pattern 21D appears in the image, the width and length of the shape of each cross type test pattern 21D is required to be concurrent, and then the person of ordinary skilled in the art should understand the width and length of each cross type test pattern 21D of the cross type 3D test chart in the predetermined space should be varied from each other.
(99) In addition, according to an embodiment of the present invention, in order to ensure that each cross type test pattern 21D can be projected to the designated viewing area in the image, the location for the image element formed corresponding to each cross type test pattern 21D in the viewing area of the image is designated, and then a back projection method is used to determine the position of each cross type test pattern 21D, so that the position and size of each cross type test pattern 21D of the test chart layer 20D of the cross type 3D test chart can be quickly obtained.
(100) After determining the position and size of each cross type test pattern 21D, it is required to analyze the error when the image element corresponding to each cross type test pattern 21D appears in the image. For example, the material of the test chart layer 20D may cause the image elements of the cross type test patterns 21D in the image to be not concurrent and not to be appear at right positions. The contrast between the cross type test pattern and the corresponding test chart layer should be determined based on the above mentioned reason and extent of the error when each cross type test pattern is projected to the image.
(101) It is worth mentioning that the media for forming each test chart layer 20D can be tangible material, or the cross type test patterns can be directly provided in the air. More specifically, as shown in
(102) It is still worth mentioning that when the design of the cross type 3D test chart is accomplished, it is required to test and analyze the application of the cross type 3D test chart. Accordingly, when the image formed by means of the cross type test patterns 21D meets the requirements, and there are no overlapping and interfering problems, then the job of the design of the cross type 3D test chart is finished. When there are interfering problems for the image formed by means of the cross type test patterns 21D, the error tolerance should be calculated again to reset the layout such as the size and density of the cross type test patterns 21D.
(103) Correspondingly, the present invention further provides a method for forming the cross type 3D test chart, wherein the method comprises the step of forming a plurality of cross type test patterns 21 in a direction along a depth thereof which do not overlap when they are projected to an image space to form an image.
(104) Preferably, the method further comprises the step of collecting the parameters and precision requirements of the photographic arrangement 10 to be tested, and determining the position configuration of the cross type 3D test chart and the number of the layers of the test chart layers 20D.
(105) More specifically, set a as the parameter which represents the precision requirement for fitting the back focus of the photographic arrangement 10 to be tested, set EFL as the parameter which represents the focal length, set h as the parameter which represent the position configuration of the cross type 3D test chart 100D, then h.sub.j represents the position of the jth layer of the test chart layers 20D, and the functional equation reflecting the position of the test chart layers is as follows: a=−((EFL*(−hj)/(EFL−hj)−(EFL*(−h)/(EFL−h))). Accordingly, based on the above functional equation, the value of h.sub.j can be calculated to determine the position of each test chart layer 20D of the cross type 3D test chart 100D.
(106) In addition, set n as the parameter which represents the number of the layers of the test chart layers 20D, set t as the parameter which represents the error tolerance of the photographic arrangement 10 which is predetermined by the manufacturing process, set s as the parameter which represents the number of the moving steps of the photographic arrangement 10, and then obtain the functional equation regarding the number of the layers of the test pattern payers 20D as follows: n=f(t,a,s). Therefore, the quantity of the test chart layers 20D can be determined by obtaining the value of n.
(107) Preferably, in the above method, when the position configuration of the cross type 3D test chart and the quantity of the test chart layers 20D are determined, the error tolerance of the material of the test chart layers 20D as well as other error tolerances may be considered to determine the layout of the cross type test patterns 21D.
(108) According to an embodiment of the present invention, set d as the parameter which represents the layout of the cross type test patterns 21D, and d.sub.ij is a parameter which represents a distance from a cross type test pattern 21D of a test chart layer 20D to a center of the test chart layer 20D, set F as the parameter which represents the testing field of view of the photographic arrangement 10, and obtain the functional equation representing the layout of the test patterns as follows: d.sub.ij=f′(F,h.sub.ij,EFL). Thus, the value of the parameter d.sub.ij can be respectively calculated based on the above formula to obtain the layout of the cross type test patterns 21D.
(109) Furthermore, set L as the parameter which represents the size of each cross type test pattern 21D and L.sub.ij can be the parameter representing the size of the ith cross type test pattern 21D of the jth test chart layer 20D, set t′ as the parameter which represents the error tolerance for manufacturing the cross type 3D test chart 100D, set n′ as the parameter which represents the index of refraction of the cross type 3D test chart 100D, set s′ as the parameter which represents the allowable disc of confusion during a calculating step of a software, set ΔF as the parameter which represents the allowable range of the span of testing field of view, and then obtain a functional equation regarding the size of the cross type test pattern 21D as follows: L.sub.ij=f″(dij,ΔF,t′,n′,s′). Accordingly, the size of each cross type test pattern 21D can be obtained by calculating the value of L.sub.ij based on the above functional equation.
(110) According to another preferred embodiment of the present invention, when designing the layout of the cross type test patterns 21A, a cross type image may be formed at first, and then uses a back projection method to obtain the configuration of the cross type 3D test chart, so that the cross type 3D test chart provide a plurality of test patterns extending along different depths.
(111) It is worth mentioning that during determining the parameters of the cross type test chart, at least one predetermined position can be determined at each test chart layer 20D, and at least one test pattern 21D is provided at the predetermined position. And then, a plurality of test chart layers 20D are overlapped in such a manner that each cross type test pattern 21D of a test chart layer 20D does not overlap with cross type test patterns 21D of other test chart layers 20D, so that there is no interfering problem in the image formed by means of the projection of the 3D test chart.
(112) According to an embodiment of the present invention, each cross type test pattern 21D can be formed on a surface of the corresponding test chart layer 20D. For example, each cross type test pattern 31D can be prepared and then is attached to the surface of the corresponding test chart layer 20D, and the plurality of test chart layers 20D are overlapped to form the cross type 3D test chart. According to another example of the present invention, each cross type test pattern 21D can be formed in the corresponding test chart layer 30D, so that the reliability of the cross type 3D test chart for testing the photographic arrangement 10 is ensured.
(113) Referring to
(114) More specifically, as a first example, referring to
(115) As a second example, referring to
(116)
(117) Referring to
(118) More specifically, referring to
(119) Referring to
(120) It is worth mentioning that the person of ordinary skilled in the art should understand that the cross type 3D test chart can be prepared by other methods, and the above cross type 3D test charts are exemplary only and do not limit the present invention.
(121) In addition, when testing the photographic arrangement 10 using the cross type 3D test chart, the testing method regarding the imaging quality can be any method, which can evaluate the imaging resolution of the photographic arrangement 10, can be selected from the group consisting of OTF (Optical Transfer Function), MTF (Modulation Transfer Function), SFR (Spatial Frequency Response), CTF (Contrast Transfer Function) and the combination thereof. Preferably, the MTF (Modulation Transfer Function) method can be used. The person of ordinary skilled in the art should understand that other methods also can be used to evaluate and test the imaging quality of the photographic arrangement 10.
(122) It is still worth mentioning that although the photographic arrangement 10 described in the specification is illustrated to comprises the photographic module 11 and the image sensor 12, the photographic module 11 may comprises one or more lens, and optionally a voice coil motor (not shown in the drawings), the image sensor 12 may be provided with a PCB board (not shown in the drawings). In other words, other possible components may be provided for facilitating the operation of the photographic module 11 and the image sensor 12.
(123) Referring to
(124) Referring to
(125) According to the present invention, before testing the photographic arrangement 10, it is a necessary step for establishing a plurality of test patterns 21 which are arranged in different depths. And then, an image with information of different depths can be obtained by shooting the test patterns 21 with the photographic arrangement 10. According to this preferred embodiment of the present invention, forming the 3D test chart of the present invention is able to provide test patterns 21 in different depths.
(126) More specifically, the 3D test chart 100 comprises a plurality of test chart layers 20 which are arranged in a direction along a depth thereof, each test chart layer 20 is provided with at least one test pattern 21, and the test pattern 21 of one test chart layer 20 does not overlap with other test patterns 21 of other test chart layers 20 arranged in different depths.
(127) After the parameters of the 3D test chart 100 are determined, the person of ordinary skilled in the art should understand the quantity of the test chart layers 20 of the 3D test chart 100 is n=j, wherein j>1. Each of the parameters h.sub.1 to h.sub.j-1 represents the pitch of each test chart layer (a distance between adjacent test chart layers). Each of the parameters from U.sub.1 to U.sub.j-1 represents the object distance of each test pattern 21, and each of the parameters from V.sub.1 to V.sub.j-1 represents the image distance of each test pattern 21. In other words, test patterns 21 of different test chart layers have different object distances and image distances. Set m.sub.in.sub.j as a parameter representing a serial number of the test pattern 21, wherein j represents the layer number of the test chart layer 20 while i represents the designated number of the test pattern 21, wherein i>1. In other words, two or more test patterns 21 can be provided at each test chart layer 20. Alternatively, each test chart layer 20 may also be provided with a single test pattern 21 in other examples. In addition, the image element corresponding to each test pattern 21 is designated as m′.sub.ij.
(128) Referring to
(129) Referring to
(130) Accordingly, the photographic arrangement 10 is placed at the initial position to shoot a picture about the test patterns 21. It is worth mentioning that the test patterns 21 of different depths of the 3D test chart will appear in the same image, so that a single image can provide information of the test patterns of different depths, and the corresponding resolution values corresponding to each test pattern 21 can be calculated out. The person of ordinary skilled in the art should understand that the different depths of the 3D test chart means different image distances can be provided. In other words, different image distances are respectively provided between the test patterns 21 of the 3D test chart 100 and the photographic arrangement 10, so that the image information can be used to provide a functional formula regarding the imaging resolution and defocus amount of each test pattern 21.
(131) Accordingly, the functional equation regarding the imaging resolution and defocus amount of each test pattern 21 is as follows:
F.sub.0=F.sub.(v){mtf.sub.(01),mtf.sub.(02),mtf.sub.(03) . . . tmf.sub.(0j)},
F.sub.j=F.sub.(v){mtf.sub.(i1),mtf.sub.(i2),mtf.sub.(i3) . . . mtf.sub.(ij)}.
(132) Set P as the parameter representing the focal point, and the person of ordinary skilled in the art is able to calculate out the focal points of the test patterns 21 as P.sub.0 to P.sub.j. P.sub.o represents the focal point of the center of test patterns 21 of the 3D test chart 100, and also P.sub.o is referred to the focusing position of the photographic arrangement 10.
(133) According to an embodiment of the present invention, after calculating out the focal point, curves F.sub.0 to F.sub.4 indicating the relationship between the imaging resolution and image distance are obtained, as shown in
(134) During the above procedure, the testing method is able to use the functional equation regarding the imaging resolution and defocus amount to calculate out the tilt vector of the photographic arrangement 10, and then the adjusting unit 200 is employed to adjust the configuration of the photographic arrangement 10, and then obtain images shown in
(135) Referring to
(136) Referring to
(137) It is worth mentioning that the focusing position and the tilt vector of the photographic arrangement 10 can be obtained based on the same image and the same functional equation. When the adjusting order is input, the adjusting platform will simultaneously accomplish the adjusting process for correcting the focusing position and the tilt of the image plane of the photographic arrangement 10, so that the efficiency for testing and adjusting the photographic arrangement 10 is greatly improved.
(138) Furthermore, after finishing the adjusting process of the photographic arrangement 10, it is required to evaluate the adjusting result to the photographic arrangement 10, so that the above steps are repeated to testing and calculating the imaging resolution. If the imaging resolution of the photographic arrangement 10 meets the requirements, then it is assumed that the adjusting process by the adjusting arrangement is effective, and then a solidifying process is carried out the fix up the photographic module 11 and the image sensor 12. If the imaging resolution of the photographic arrangement 10 does not meet the requirements, then it is assumed that the adjusting process by the adjusting arrangement is not enough, a subsequent adjusting process should be carried out. It is worth mentioning that according to an embodiment of the present invention, when excessive adjusting steps, for example three times, are carried out but the desired adjusting effect still cannot be achieved, then there may be serious problem in the photographic arrangement 10, so that no further adjusting steps need to be carried out.
(139) Accordingly, as shown in
(140) (a) Configure a plurality of test patterns 21 in a direction along a depth thereof to provide a plurality of scenes of different depths.
(141) (b) Capture the image information of the plurality of test patterns 21 though shooting the 3D test chart 100 by the photographic arrangement 10.
(142) (c) Based on the image information, obtain a focal position of the photographic module 11, and a tilt vector of the photographic module and the image sensor 12, and determine the relative position of the photographic module 11 and the image sensor 12.
(143) Preferably, as shown in
(144) Preferably, in the step (a), the method further comprises the steps of: (a.1) collecting the parameters of the photographic arrangement 10 to determine the position configuration of the 3D test chart 100; and (a.2) Determining a quantity of the test chart layers, configuring a layout of the test patterns of the test chart layers based on precision requirements of the photographic arrangement 10. In addition, the method may still comprise a step of (a.3): determining a size of each test pattern.
(145) Accordingly, as shown in
(146) (α) Capture information of scenes of different depths of a 3D test chart, determine a relative position of a photographic module 11 and an image sensor 12 of the photographic arrangement 10, and obtain related data corresponding to the relative position.
(147) (β) Based on the related data, accomplish an adjusting process of the photographic module 11 and the image sensor 12.
(148) Preferably, the method may comprise the step of obtaining an image containing the information of scenes of different depths through shooting the test patterns 21 of the 3D test chart 100, wherein the plurality of test patterns 21 of the 3D test chart 100 do not overlap with each other, and two adjacent test patterns in the direction along the depth are spacedly arranged with each other.
(149) One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.
(150) It will thus be seen that the objects of the present invention have been fully and effectively accomplished. The embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.