METHOD FOR PRODUCING A CORRECTED IMAGE AND APPARATUS

Abstract

Corrected images are produced with an apparatus that includes a detector and a control unit. In a first operating mode, a plurality of image tiles of an object are captured as a plurality of image pixels. The control unit generates commands to capture each image, such that it partially overlaps with at least one other image tile in an image tile overlap region having a minimum size. Each captured image tile and/or a resultant image is combined pixel-wise by calculation in a brightness correction image. In a second operating mode, the brightness correction image is produced by capturing a plurality of correction image tiles of the object as a plurality of image pixels, and control commands are generated, so the object is moved relative to a detection beam path and a size of a correction image overlap region is greater than the minimum size of the image tile overlap region.

Claims

1-10. (canceled)

11. A method for producing a corrected image by using an apparatus for image capturing, wherein the apparatus has a detection beam path with a detector and a control unit for generating control commands; the method comprising: in a first operating mode: capturing a plurality of image tiles of an object present in a sample chamber, wherein each of the image tiles is captured as a plurality of image pixels; generating control commands with the control unit to cause each of the image tiles to be captured in a manner such that the image tile partially overlaps with at least one further captured image tile in an image tile overlap region of a defined minimum size; producing a resultant image by stitching the image tiles, wherein image data of the plurality of image pixels of the overlap regions are used to arrange the tile images at a correct position and with a correct orientation relative to one another; and correcting each of the captured image tiles and/or the resultant image by means of a brightness correction image, wherein each image pixel of the image tiles and/or of the resultant image is combined by calculation with image data from corresponding pixels of the brightness correction image; and in a second operating mode: producing the brightness correction image by capturing a plurality of image tiles of the object in each case as a plurality of image pixels, wherein control commands are generated by the control unit such that the object is moved relative to the detection beam path and a size of a correction image overlap region is greater than the minimum size of the image tile overlap region.

12. The method according to claim 11, wherein the control commands serve for controlling a drive unit by means of which the object can be moved and the size of the correction image overlap region in one image direction is selected to be greater than 10% of an extent of the image tiles in said image direction.

13. The method according to claim 11, further comprising analyzing a currently available brightness correction image in respect of a quality criterion defined in advance; and when the quality criterion is not satisfied, combining the currently available brightness correction image by calculation with a further image tile of the object.

14. The method according to claim 13, wherein the size of the correction image overlap region is in each case selected based on the result of an assessment of the quality criterion.

15. The method according claim 11, wherein the object includes a sample holder.

16. The method according to claim 11, wherein the object includes a sample having molecules emitting detection radiation to be captured.

17. The method according to claim 11, further comprising illuminating the object with transmitted light.

18. The method according to claim 11, further comprising capturing the image tiles for producing the brightness correction image with time-limited illumination of the object.

19. The method according to claim 11, further comprising moving the object for capturing an image tile by a specific path length to a position specified by a control command and is stopped there, at which position a further image tile for producing the brightness correction image is captured.

20. An apparatus for capturing images of an object present on an adjustable sample stage in a sample chamber, the apparatus comprising: a detection beam path; a detector; and a control unit configured for generating control commands; wherein in a first operating mode, the control unit is configured to generate control commands to control the detector and the sample stage so as to capture a plurality of image tiles of the object, and to, after an image tile has been captured, move the object relative to an optical axis of the detection beam path by a defined path length that is less than an extent of the captured image tile in a movement direction so that each of the tile images partially overlaps with at least one further captured tile image in an image tile overlap region of a defined minimum size, and wherein in a second operating mode, the control unit is configured to generate control commands to control the sample stage so as to move the object, after an image tile has been captured, relative to the optical axis of the detection beam path by a path length that is less than the defined path length of the first operating mode so that a minimum size of a correction image overlap region is greater than the minimum size of an image tile overlap region.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The invention will be explained in more detail below on the basis of drawings. In the figures:

[0034] FIG. 1 shows a schematic example of producing a brightness correction image in accordance with the prior art;

[0035] FIG. 2 shows a schematic illustration of a refinement of the method according to the techniques described herein; and

[0036] FIG. 3 shows a schematic illustration of an exemplary embodiment of an apparatus according to the techniques described herein.

DETAILED DESCRIPTION

[0037] A method known from the prior art for producing a brightness correction image KB (also referred to as a correction image KB for short) is illustrated highly schematically in FIG. 1. A number of (correction) image tiles TB1, TB2 to TBn are captured, the respective pixels of the image tiles are combined by applying different mathematical methods optionally to be selected (symbolized by the character sequence: Σ/n), for example averaging, and this is used to create the correction image KB. It is evident that the correction image KB has a smaller variance in its brightness intensity values and appears more homogeneous than is the case for the first image tile TB1, for example.

[0038] A refinement of the method according to the techniques described herein is illustrated in FIG. 2. A resultant image rB, which has been stitched from a plurality of image tiles (not shown) and illustrates a sample 2, is shown merely for explanatory reasons. A first to n.sup.th image tile TB1 to TBn, which overlap one another in one of their extents, in the illustrated case in the horizontal image direction, are shown by way of example. The correction image overlap regions Ov (overlap) that arise in the process are shown by way of example. The correction image overlap regions Ov are selected to be greater, in particular, greater than 10%, than would be the case with imaging of the sample 2 for the purpose of producing a resulting image rB. The correction image KB is produced by means of a mathematical method from the image tiles TB1 to TBn that partially overlap one another. In this case, each of the image tiles TB1 to TBn has for example a respective variance with a value ranging from 18 to 80, while the variance of the correction image KB produced is only 3, for example.

[0039] An exemplary embodiment of an apparatus for carrying out the method according to the invention is illustrated schematically in FIG. 3. A sample 2 can be arranged on a controllably adjustable sample stage 1. Said sample is illuminated by means of a light source 3. Detection radiation emanating from the sample 2, for example, fluorescence radiation and/or reflected components of the illumination radiation, is captured by means of an objective lens 4 and imaged along an optical axis (symbolized by a discontinuous line) onto a spatially resolved detector 5, for example a CCD, CMOS or sCMOS chip, a SPAD (single photon avalanche diode) array or an array of a plurality of PMTs (photomultiplier tubes). The image data captured by means of the detector 5 are transmitted to an evaluation unit 8 and combined there by calculation to form a resultant image rB or a correction image KB.

[0040] In alternative embodiments of the apparatus, the illumination can be implemented in transmitted light, that is to say, for example, in the bright field, by means of the light source 3 then positioned appropriately (shown in exemplary and optional fashion using a discontinuous line).

[0041] In addition, a control unit 6, which, for example, may be in the form of a computer or of an FPGA and which is configured to generate control commands, is present. The control commands are generated such that the above-described two operating modes are, or can be, executed. The control unit 6 is connected in each case to a drive unit 7 for motor-driven movement of the sample stage 1, to the detector 5, and to the light source 3 in a manner suitable for the transfer of data.

[0042] The evaluation unit 8 may be optionally connected to the control unit 6, for example to facilitate an adaptation of the control commands generated there on the basis of the captured image data or on the basis of the degree of fulfillment of selected quality criteria.

[0043] List of reference signs

[0044] 1 Sample stage

[0045] 2 Sample, object

[0046] 3 Light source

[0047] 4 Objective lens

[0048] 5 Detector

[0049] 6 Control unit

[0050] 7 Drive unit

[0051] 8 Evaluation unit

[0052] TB1, . . . , TBn First image tile, . . . , n-th image tile

[0053] Ov (Correction image) overlap region

[0054] rB Resultant image/overall image

[0055] KB Brightness correction image