SINGLE-FIBER COLOR IDENTIFICATION
20220404200 · 2022-12-22
Assignee
Inventors
- Rejoy Isaac (Westwood, NJ, US)
- Marsha Ann Spalding (Hampton, NJ, US)
- Bryce Currier (Dover, NH, US)
- Geraldine Paraiso (Eatontown, NJ, US)
- Ralph J. Rue (Barnegat, NJ, US)
Cpc classification
G01M11/30
PHYSICS
International classification
G01J3/46
PHYSICS
Abstract
Disclosed are a system and techniques to determine a color of an optical fiber in a fiber optic cable. A spectrophotometer camera may obtain a color value of the optical fiber. A fiber adaptor is operable to hold a single optical fiber of a fiber optic cable in a field of view of the spectrophotometer camera. A memory storing instructions that, when executed by a processor, enable identifying a color of the optical fiber. The color value may be compared to a color value of a number of reference colors. A color match score value may be generated for the color value with respect to each reference color. A confidence value may be obtained for a pair of color match scores that are closest in score value. Based on the confidence value, one of the reference colors is identified as a color of the optical fiber.
Claims
1. A method, comprising: obtaining, by a processor, a color value of an optical fiber in a fiber optic cable from a spectrophotometer camera; comparing the color value of the optical fiber to a color value of each reference color of a plurality of reference colors, wherein each reference color has a unique color value; generating a color match score for the color value of the optical fiber with respect to the color value of each reference color of the plurality of reference colors based on a result of the comparing, wherein the color value of each reference color is different for each reference color and the color match score has a score value; obtaining a confidence value for a pair of color match scores that are closest in score value; and identifying, based on the confidence value, one of the reference colors from the plurality of reference colors as a color of the optical fiber.
2. The method of claim 1, wherein generating the color match score further comprises: utilizing a first algorithm to determine a first color match score; and utilizing s second algorithm to determine a second match score.
3. The method of claim 2, wherein determining the first color match score comprises: accessing a database having a plurality of color entries, wherein each color entry of the plurality of color entries has a respective color value; and determining a first color match score for the obtained color value of the optical fiber with each color entry of the plurality of color entries.
4. The method of claim 2, wherein determining the first color match score comprises: measuring a Euclidean distance between three coordinates in a color coordinate space for the obtained color value.
5. The method of claim 2, wherein determining the second color match score comprises: obtaining a reflectance spectra value using the obtained color value.
6. The method of claim 1, wherein identifying, based on the confidence value, the one reference color from the plurality of reference colors as the color of the optical fiber, further comprises: determining which reference color has a largest confidence value; and indicating the reference color with the largest confidence value as the color of the fiber optic cable.
7. The method of claim 6, further comprising: generating a ratio of two color match scores having scores that most closely match a reference color value; and assigning the ratio as the confidence value.
8. A system, comprising: a spectrophotometer camera; a fiber adaptor operable to hold a single optical fiber of a fiber optic cable in a field of view of the spectrophotometer camera; a processor; and a memory storing instructions that, when executed by the processor, configure the processor to: obtain a color value of the single optical fiber in the fiber optic cable from the spectrophotometer camera; compare the color value of the optical fiber to a color value of each reference color of a plurality of reference colors, wherein each reference color has a unique color value; generate a color match score for the obtained color value of the optical fiber with respect to the color value of each reference color of the plurality of reference colors based on a result of the comparing, wherein the color value of each reference color is different for each reference color and the color match score has a score value; obtain a confidence value for a pair of color match scores that are closest in score value; and identify, based on the confidence value, one of the reference colors from the plurality of reference colors as a color of the optical fiber.
9. The system of claim 8, wherein generating the color match score further comprises: utilize a first algorithm to determine a first color match score; and utilize s second algorithm to determine a second match score.
10. The system of claim 9, wherein determining the first color match score comprises: access a database having a plurality of color entries, wherein each color entry of the plurality of color entries has a respective color value; and determine a first color match score for the obtained color value of the optical fiber with each color entry of the plurality of color entries.
11. The system of claim 9, wherein determining the first color match score comprises: measure a Euclidean distance between three coordinates in a color coordinate space for the obtained color value.
12. The system of claim 9, wherein determine the second color match score comprises: obtain a reflectance spectra value using the obtained color value.
13. The system of claim 8, wherein identifying, based on the confidence value, the one reference color further comprises: determine which reference color has the largest confidence value; and indicate the reference color with the largest confidence value as the color of the fiber optic cable.
14. The system of claim 13, wherein the instructions further configure the processor to: generate a ratio of two color match scores having scores that most closely match a reference color value; and assign the ratio as the confidence value.
15. A non-transitory computer-readable storage medium, the computer-readable storage medium including instructions that when executed by a processor, cause the processor to: read a sample color from an optical fiber in a fiber optic cable, wherein the sample color has a color value; select a color match algorithm from a plurality of color matching algorithms; input the color value into a selected color match algorithm, wherein the selected color matching algorithm processes the inputted color value with respect to a plurality of reference colors; generate for each reference color of the plurality of reference colors a color match score using the selected color matching algorithm; generate a confidence value based on a ratio of scores of two closest matched colors; if another color match algorithm from the plurality of color matching algorithms is available for selection, performing the selecting, the inputting, the generating of another color match score, and the generating another confidence value; when no other color match algorithm is available, determine a largest confidence value from the generated confidence values; select a color corresponding to the determined largest confidence value as the color of the optical fiber in the fiber optic cable; and generate an output indicate the selected color.
16. The non-transitory computer-readable storage medium of claim 15, further causes the processor when generating a color match score to: utilize a first algorithm to determine a first color match score; and utilize s second algorithm to determine a second match score.
17. The non-transitory computer-readable storage medium of claim 16, further causes the processor when determining the first color match score to: access a database having a plurality of color entries, wherein each color entry of the plurality of color entries has a color value; and determine a first color match score for the obtained color value of the optical fiber with each color entry of the plurality of color entries.
18. The non-transitory computer-readable storage medium of claim 16, further causes the processor when determining the first color match score to: measure a Euclidean distance between three coordinates in a color coordinate space for the obtained color value.
19. The non-transitory computer-readable storage medium of claim 16, further causes the processor when determining the second color match score to: obtain a reflectance spectra value using the obtained color value.
20. The non-transitory computer-readable storage medium of claim 15, further causes the processor when identifying, based on the confidence value, the one reference color to: determine which reference color has the largest confidence value; and indicate the reference color with the largest confidence value as the color of the fiber optic cable.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced.
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DETAILED DESCRIPTION
[0030] The disclosed system, devices and processes demonstrate novel techniques to apply an existing colorimetry technology to identify color on a very small surface of an optical fiber. The solution is optimized for field applications: cost-effective, does not require an elaborate setup, provides instant results, reliable, non-destructive and needing less than approximately 2″ of fiber length.
[0031] A quantitative approach as presented herein eliminates the over-reliance on a human operator to discern fiber colors, which can significantly reduce errors. This would provide considerable time and cost-savings by minimizing cross-splices and improves overall production quality.
[0032] The described examples have the advantage of requiring almost no sample preparation of the fiber unlike the traditional array-based fiber color measurements which requires at least ˜1 meter of sacrificial fiber lead as well as substantial operator time to create the fiber array.
[0033] The techniques outlined herein describe how a color spectrophotometer can be used to uniquely identify the color on a single fiber.
[0034] The described solution is a mechanism to accurately identify color of a single strand of optical fiber in a way that is suitable (quick, portable, and easy to use) for use in a factory or cable ship environment.
[0035] An example spectrophotometer, such as camera 102, quantifies the color by representing it in terms of three values: L* (lightness), a* (red-green), and b* (blue-yellow) in the 3-dimensional CIE rectangular color space. Of course, other color spaces may be used, such as RGB, HSV, HSL, YPbPr or the like. Additionally, the spectrophotometer camera 102 also records the spectrophotometric curve, which is the amount of reflected light at each wavelength between 400 nm and 700 nm (range of visible light) for each sample measurement. Both the L*, a*, b* values and the values of the spectrophotometric curve data for a given fiber sample measurement may be used to determine the optical fiber color by matching the obtained color value data to a look-up table with pre-determined reference values for each optical fiber color used when building a fiber optic cable. Examples of the colors of the optical fibers used in fiber optic cables may include red, blue, yellow, brown, green, orange, violet, black, rose, aqua, olive, white, lime, tan, magenta, grey, natural, dark green, lavender, purple, sky, pink, peach and saffron.
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[0039] The fiber adaptor 202 is shown as circular and the aperture 104 of
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[0041] In an operational example, the fiber-under-test (204) is threaded through the openings 208 in the fiber adapter (202). The fiber groove 212 in the adapter is directly above the circular aperture (4). This ensures repeatable placement of the fiber sample (1) over the circular aperture (4). The opaque inner surface of cove 210 of the fiber adaptor 202 is operable to ensure that the region outside the fiber surface is effectively blocked from affecting the sampling of the fiber 204. The fiber adaptor 202 is placed onto the spectrophotometer 2 mm aperture, such as 302 shown in
[0042]
[0043] The fiber adaptor 214 includes an optical fiber trough 216 and guide 218. The guide 218 enables an operator to insert a single optical fiber (not shown in this example) into the optical fiber trough 216. The fiber adaptor 214 with the single optical fiber in the optical fiber trough 216 may be affixed to a spectrophotometer camera, such as that shown in the disclosed examples. The fiber adaptor 214 is operable to hold the single optical fiber in the field of view of the spectrophotometer camera with a modified aperture as shown in other examples.
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[0046] Of course, other configurations of a fiber adaptor 214 may be utilized with an intended purpose being to maintain the optical fiber in a position that enables sufficient sampling to enable consistent and accurate identification of the single optical fiber being sampled.
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[0049] In step 402, a processor may read a sample color from an optical fiber in a fiber optic cable, where the sample color has a color value. The color value may be an L*a*b* color value, such as 24.722, 11.480 and 3.862 for red or the like for other colors.
[0050] In step 404, the processor may select a color matching algorithm from a plurality of color matching algorithms for use in determining the color match for the single optical fiber.
[0051] In step 406, after selection of the color matching algorithm, the processor may input the color value into a selected color matching algorithm. The selected color matching algorithm processes the inputted color value with respect to a plurality of reference colors and generates a color match score for each reference color of the plurality of reference colors.
[0052] In step 408, the processor may generate a confidence value based on a ratio of color match scores of two closest matched colors. For example, the processor may utilize two of the closest match scores in a ratio to determine the confidence value. The confidence value is an example of how the color distinction may be measured. The generation of the confidence value is described in more detail below.
[0053] The processor, at step 410, may determine if another color matching algorithm from the plurality of color matching algorithms is available for selection, selecting the other color matching algorithm. If the response to the determination at step 410 is YES, the process 400 may proceed to step 414.
[0054] At step 414, the processor may input a color value into the other selected color matching algorithm to generate another color match score using the other selected color matching algorithm. The processor may use the other color match score output from the other selected color matching algorithm to generate another confidence value. When no further color matching algorithms are available, each confidence value generated based on a respective color match score from each color matching process may be evaluated.
[0055] When the response to the determination at step 410 is No, another color matching algorithm is not available, the process may proceed to step 412. At step 412, the processor may select a color corresponding to the determined highest confidence value as the color of the optical fiber in the fiber optic cable. The processor may generate an output indicating the selected color.
[0056] Alternatively, instead of determining a confidence value, the color matching scores may be normalized between the different color matching algorithms. An alternative color matching algorithm may include the steps of creating or obtaining by a processor a color reference database, such as Color[ ], by measuring samples of fiber colors. Once a color reference database is available for use by the processor. The processor may be operable, in response to a user input or automatically, when an optical fiber is detected as being in place, the processor may be operable to take a color measurement of the fiber sample under test. The processor may use a first color matching algorithm (discussed with reference to another figure) to determine the closest matched color, X, and corresponding Matching Score_X. The processor may return the color name X and a value for the Matching Score_X (e.g., Violet and 85). The processor in the alternative example, may use a second color matching algorithm to determine the closest matched color. In the second color matching algorithm, the processor may determine the closest matched color name, Y, and corresponding Matching Score_Y (e.g., Lavender and 83). To determine the color, the processor may evaluate or compare the Matching Score_X to the Matching Score_Y. Based on the result of the evaluation or comparison, the processor may select a color as the color of the optical fiber and generate an output indicating the selected color. For example, if (Matching Score_X>Matching Score_Y), the selected color=X; Else, the selected color=Y. Using this logic and the results above, Matching Score of Violet=85, while the Matching Score of Lavender is 83. In this case, the selected color of the optical fiber would be Violet. In another operational example, Algorithm 1 may give the closest matching colors as: Peach (Score: 0.1) and Pink (Score 2). Confidence score=2/0.1=20 for the color Algorithm 1. If for the same fiber, Algorithm 2 gives the closest matching colors as: Pink (Score: 0.5) and Magenta (Score: 1). Confidence score=1/0.5=2. So, the processor may determine the matching color is peach based on the highest confidence score from Algorithm 1.
[0057] Other color matching algorithms may also be used, and another example is described with reference to
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[0059] A database of N color entries 502 may store color coordinate values (e.g., L*a*b*) and reflectance spectrum space values S[λ.sub.1-λ.sub.N]. At step 504, the processor may receive a measured color sample with values for L.sub.i*, a.sub.i*, b.sub.i* and S[λ.sub.i]. The processor at 506 may calculate a color match score for each color 1-N in the database, where ‘i’ is the respective color match score for each respective color [1 to N] in the database.
[0060] The processor may calculate the color match score as follows: Color Match Score, =sqrt((a*−a.sub.i*).sup.2+(b*−b.sub.i*).sup.2+(S[λ.sub.0]−S.sub.i[λ.sub.0]).sup.2), where subscript ‘i’=1 to N, where N is the total number of entries in the color reference database, and the reflectance spectrum space value S[λ.sub.0] is the reflectance value at a given wavelength for the color sample under test and S.sub.i[λ.sub.0] is the reflectance spectrum value of the reference color from the color entry database.
[0061] In the example, the processor may sort the colors from the color entry database as color[1-N] from closest matched to least matched based on the calculated color match score.sub.i, where the smallest color match score corresponds to the closest match of the measured color sample to the reference color in the color entry database of N color entries 502. Continuing with this example, the matching color may be color X, e.g., Matching Color, X=Color [1]. The Color [1] may have a matching color score of 9, for example. The processor may determine another color having a next smallest matching color score (i.e., a color match score of 11). The processor may then determine a color matching score, which is a final score used by the algorithm, using the smallest matching color score and the next smallest matching color score. For example, the processor may determine the matching color score by taking the ratio of the matching color scores of the 2 closest matched colors for color X or color [1] in the color entry database of N color entries 502: Matching Color Score_X=Score.sub.i[2]/Score.sub.i[1].
[0062] The algorithm performs the same operation for each color 1-N in the database of N color entries 502. The output of process 500 being the ratio of matching color scores that produces the lowest value, may be provided for use in process 400. For example, the result of the algorithm may be output for further processing by the processor such as step 412 in process 400.
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[0064] To account for amplitude variations, for example, based on the fiber adaptor, the spectra being compared are first normalized. The color comparison is then done using 3 parameters: the Euclidean distance between the two normalized spectra, average value of the reflectance spectra and the magnitude of the range (max−min) of reflectance spectra. Details of the normalization and the subsequent color matching is shown in
[0065] In the example, S[λ] represents an array of reflectance values at different wavelengths. max(S[λ]) is the largest reflectance value and min (S[λ]) is the smallest. The two values are at different wavelengths (unless the spectrum is a flat line, which is not normally the case). At measure color sample step 602, the processor may receive a measure color sample of an optical fiber sample under test. The measured color sample may include color space L*, a*, b* values as well as a reflectance spectrum space value, S[λ.sub.0], where S[λ.sub.0] is the reflectance value at a wavelength λ.sub.0 which returns the largest spectral response. Of course, other color spaces, such as those described above, may be used. The reflectance spectrum 604 may be obtained from the measured color sample from step 602. At normalization step 606, the processor may determine a normalized reflectance, S′ [λ] of the optical fiber sample under test (as shown in cloud 606/614), using the following: S′ [λ]=(S [λ]−Avg_S)/(Range_S/2), here Avg_S=average(S[λ]) AND Range_S is the difference between a maximum reflectance value and a minimum reflectance value (e.g., Range_S=max(S[λ])−min (S[λ])).
[0066] The processor at normalization of reference color spectrum 614 also determines a normalized reflectance value for the color entries in the database with color entries 610. The database with color entries 610 may include reference colors to which the measures color samples are matched. For example, for each color, T in the database with color entries 610, the processor by executing code for implementing the color matching algorithm, may calculate: a normalized reflectance, S′.sub.j[λ], an average reflectance (Avg_S.sub.j), and a range of reflectance (Range_S.sub.j). The determinations are similar to the reflectance spectrum normalization step 606 determinations.
[0067] The results of the normalization step 606 for the measured color sample and the normalization of reference color spectrum 614, the processor may calculate a color match score for each color, T in the database, as follows: Score.sub.j=ΔS.sub.j*(1+ΔAvg+ΔRange), where ΔS.sub.j=Σ(S′[λ]−S′.sub.j[λ]).sup.2, ΔAvg=abs (Avg_S−Avg_S.sub.j) and ΔRange=abs (Range_S−Range_S.sub.3).
[0068] In response to obtaining a color match processor may sort the colors, for example, Color [j] from closest matched to least matched based on the calculated Score.sub.3. The smallest Score corresponds to the closest match. For example, the smallest score may be for color Y, e.g., Matching Color, Y=Color [3]. In the example, the Color [3] may have a matching color score of 8, for example. The processor may determine another color having a next smallest matching color score (i.e., a color match score of 10). The processor may then determine a color matching score, which is a final score used by the algorithm, using the smallest matching color score and the next smallest matching color score. For example, the processor may determine the matching color score by taking the ratio of the matching color scores of the 2 closest matched colors for color Y or color [3] in the database of N color entries 502: Matching Score_Y=Score.sub.j[λ.sub.0]/Score.sub.j[3].
[0069] The algorithm performs the same operation for each color 1-N in the database of N color entries 610. The output of process 600 being the ratio of matching color scores that produces the lowest value, may be provided for use in process 400. For example, the result of the algorithm may be output for further processing by the processor such as step 412 in process 400.
[0070]
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[0072] In block 804, the processor may be operable to compare the color value of the fiber optic cable to a color value of each reference color of a plurality of reference colors, wherein each reference color has a unique color value.
[0073] In block 806, the processor generates a color match score for the color value of the fiber optic cable with respect to the color value of each reference color of the plurality of reference colors based on a result of the comparing, wherein the color value of each reference color is different for each reference color and the color match score has a score value. For example, generating a color match score further includes utilizing a first algorithm to determine a first color match score, and utilizing s second algorithm to determine a second match score. In an example, when determining the first color match score, a process may include accessing a database having a plurality of color entries, wherein each color entry of the plurality of color entries has a color value. A first color match score for the obtained color value of the optical fiber may be determined with respect to each color entry of the plurality of color entries. In addition, determining the first color match score may include measuring a Euclidean distance between three coordinates in a color coordinate space for the obtained color value or obtaining a reflectance spectra value using the obtained color value.
[0074] In block 808, the processor obtains a confidence value for a pair of color match scores that are closest in score value. The process of block 808 may be similar to the processes for obtaining a confidence value as described with reference to the processes 400 and 500.
[0075] In block 810, the processor may identify, based on the confidence value, one of the reference colors from the plurality of reference colors as a color of the fiber optic cable. For example, identifying, based on the confidence value, one of the reference colors may further include determining which reference color has the largest confidence value, and indicating the reference color with the largest confidence value as the color of the fiber optic cable. In a further example, the identifying may include generating a ratio of two color match scores having scores that most closely match a reference color value and assigning the ratio as the confidence value. Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions, and claims.
[0076]
[0077] The spectrophotometer camera 902 may be a camera system 100 operable to collect color data from an optical fiber of a fiber optic cable, such as the camera 102 of
[0078] In an example, the processor 904 is operable to execute programming code 912 to provide the optical fiber color identification processes described with reference to the examples of
[0079] The input/output device 906 may be a touchscreen display of a mobile device, a tablet computing device, a laptop, a dedicated computing device or the like. Alternatively, the input/output device 906 may be a display device coupled to a keyboard, touchpad, mouse or the like. The processor via the input/output device 906 may be operable to receive changes to settings and parameters in the color entry database 910 or the color matching algorithms.
[0080] The various elements of the devices, apparatuses or systems as previously described with reference to
[0081] Herein, novel and unique techniques for an improved inspection of cables and cable joints are disclosed. The present disclosure is not to be limited in scope by the specific examples described herein. Indeed, other various examples of and modifications to the present disclosure, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings.
[0082] Thus, such other examples and modifications are intended to fall within the scope of the present disclosure. Further, although the present disclosure has been described herein in the context of a particular implementation in a particular environment for a particular purpose, those of ordinary skill in the art will recognize that its usefulness is not limited thereto and that the present disclosure may be beneficially implemented in any number of environments for any number of purposes. Accordingly, the claims set forth below should be construed in view of the full breadth and spirit of the present disclosure as described herein.