Automatic test system for optical transfer function

Abstract

The invention provides an automatic test system for an optical transfer function. The automatic test system comprises a detector, a light emitting module, a collimator and a processing module, wherein one side of the detected optical system is aligned with a light outlet of the collimator, the detector is arranged on the other side of the detected optical system, emergent light of the light emitting module passes through the collimator to form parallel light to irradiate one side of the detected optical system, and the emergent light is received by the detector and is imaged; and the processing module is used for acquiring imaging data of the detector, performing automatic focusing on the detector according to an imaging condition to make an imaging image clear, adjusting the position of the light emitting module to be aligned with the detector, automatically acquiring the imaging data of the detector, performing optical transfer function calculation, and displaying a calculation result. According to the invention, automatic testing of optical transfer function can be carried out, the testing is rapid, accurate and high in repetition precision, and the whole system is integrated by adopting general equipment, so that testing is convenient to build, and the cost is saved.

Description

Technical Field

[0001] The invention relates to the technical field of optical measurement, and in particular to an automatic testing system for optical transfer functions. Background Art

[0002] With the widespread application of optical systems in various fields, the requirements for imaging quality are getting higher and higher. The optical transfer function is an important parameter for evaluating the imaging quality of optical systems.

[0003] In the related art, the optical transmission function test method requires testing based on visual measurement, manual interpretation, and manual data processing, which is inefficient and complicated to operate. In addition, the test equipment is costly and the operating steps are complicated. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides an automatic testing system for optical transfer function.

[0005] The technical solution adopted by the present invention is as follows:

[0006] The first aspect of the present invention proposes an automatic optical transfer function testing system, comprising: a detector, a light emitting module, a collimator and a processing module; wherein one side of the optical system to be tested is aligned with the light outlet of the collimator, and the detector is arranged on the other side of the optical system to be tested, and the output light of the light emitting module passes through the collimator to form parallel light to illuminate one side of the optical system to be tested, and the output light on the other side of the optical system to be tested is received by the detector and imaged; the processing module is used to obtain imaging data of the detector, automatically focus the detector according to the imaging situation to make the imaging image clear, and after adjusting the position of the light emitting module to align with the detector, automatically collect the imaging data of the detector, calculate the optical transfer function according to the imaging data, and display the calculation results.

[0007] The optical transfer function automatic testing system proposed in the present invention also has the following additional technical features:

[0008] According to one embodiment of the present invention, the light emitting module includes: a light source; a slit plate, arranged directly in front of the light source; a graticule switching device, the graticule switching device is used to switch the slit angle resolution of the slit plate; and a tilt adjustment platform, the tilt adjustment platform is used to adjust the slit tilt angle of the slit plate.

[0009] According to one embodiment of the present invention, the processing module is specifically used to: switch the slit angular resolution of the slit plate by controlling the graticule switching device so that the slit size corresponds to the angular resolution of the optical system under test; automatically identify the slit tilt angle of the slit plate, adjust the tilt angle of the tilt adjustment platform according to the slit tilt angle, and adjust the lateral displacement of the tilt adjustment platform so that the slit coincides with the horizontal and vertical pixels of the detector.

[0010] According to one embodiment of the present invention, the above-mentioned automatic optical transfer function testing system also includes: an adjustment platform, the optical system under test is fixed on the adjustment platform, and the adjustment platform is used to adjust the azimuth and pitch angles of the optical system under test; the processing module is also used to adjust the azimuth and pitch angles of the optical system under test by controlling the adjustment platform to set different fields of view, and calculate the optical transfer functions of the on-axis and off-axis fields of view of the optical system under test.

[0011] According to an embodiment of the present invention, the processing module calculates the optical transfer function according to the following formula:

[0012]

[0013] Where MTF stands for the optical transfer function, DN max Represents the bright fringe pixel signal, DN min represents the dark fringe pixel signal, and DN represents the background noise.

[0014] According to one embodiment of the present invention, the entire system is mounted on an optical platform.

[0015] The present invention has the following beneficial effects:

[0016] The present invention can automatically test the optical transmission function quickly, accurately and with high repetition precision, and the whole system is integrated with universal equipment, which is convenient for setting up the test and saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of an automatic optical transfer function testing system according to an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of a case where a slit and a detector are tilted according to an embodiment of the present invention;

[0019] Figure 3 is a schematic diagram of a case where there is a lateral displacement deviation between the slit and the detector according to an embodiment of the present invention;

[0020] Figure 4 is a schematic diagram of imaging during the adjustment process of a light emitting module according to an embodiment of the present invention;

[0021] Figure 5 The figure is a flow chart of the working process of the automatic optical transfer function testing system according to one embodiment of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] The following is a description of an automatic optical transfer function testing system provided by an embodiment of the present invention in conjunction with the accompanying drawings.

[0024] Figure 1 FIG. 1 is a schematic diagram of the structure of an automatic optical transfer function test system according to an embodiment of the present invention. Figure 1 As shown, the system includes: a detector 1, a light emitting module 2, a collimator 3 and a processing module 4.

[0025] Among them, one side of the optical system 5 to be measured is aligned with the light outlet of the collimator 3, and the detector 1 is arranged on the other side of the optical system 5 to be measured. The output light of the light emitting module 2 passes through the collimator 3 to form parallel light and irradiates one side of the optical system 5 to be measured, and the output light on the other side of the optical system 5 to be measured is received by the detector 1 and imaged; the processing module 4 is used to obtain the imaging data of the detector 1, automatically focus the detector 1 according to the imaging situation to make the imaging image clear, and after adjusting the position of the light emitting module 2 to be aligned with the detector 1, automatically collect the imaging data of the detector 1, calculate the optical transfer function according to the imaging data, and display the calculation results.

[0026] Specifically, according to Figure 1As shown, an automatic test system is constructed, and the optical system 5 to be tested is aligned with the light outlet of the collimator 3. After the outgoing light of the light emitting module 2 passes through the collimator 3 to form parallel light and irradiates the optical system 5 to be tested, its outgoing light is received by the detector 1 and imaged. The processing module 4 obtains the imaging data of the detector 1 in real time, and automatically focuses the detector according to the imaging situation until the image is clear. The following methods can be sampled to determine whether the image is clear: image clarity evaluation algorithm, edge detection algorithm, spectrum energy analysis, etc., and then the position of the light emitting module is adjusted to align with the detector to ensure that the image plane position is accurate, and then the imaging data of the detector is automatically collected. The imaging data includes pixel signals, and the optical transfer function is calculated according to the imaging data, and the calculation results are displayed. Therefore, the present invention can perform automatic testing of optical transfer functions, which is fast, accurate, and has high repeatability. The test is fast, accurate, and has high repeatability. The entire system is integrated using general equipment, which is convenient for building and testing, and saves low costs.

[0027] In a specific embodiment of the present invention, the processing module 4 can specifically calculate the optical transfer function according to the following formula:

[0028]

[0029] Where MTF stands for optical transfer function, DN max Represents the bright fringe pixel signal, DN min Represents the dark fringe pixel signal, and DN represents the background noise. max and DN min The imaging data of the detector collected by the detector can be obtained.

[0030] In one embodiment of the present invention, the light emitting module 2 includes: a light source 201, a slit plate 202, a graticule switching device 203 and a tilt adjustment platform 204. The light source 201 can emit visible light or infrared light to illuminate the slit plate 202, and the slit plate 202 is arranged directly in front of the light source 201; the graticule switching device 203 is used to switch the slit angle resolution of the slit plate 202; and the tilt adjustment platform 204 is used to adjust the slit tilt angle of the slit plate 202.

[0031] Furthermore, the processing module 4 is specifically used to: switch the slit angular resolution of the slit plate 202 by controlling the graticule switching device 203 so that the slit size corresponds to the angular resolution of the optical system under test; automatically identify the slit tilt angle of the slit plate 202, adjust the tilt angle of the tilt adjustment platform 204 according to the slit tilt angle, and adjust the lateral displacement of the tilt adjustment platform 204 so that the slit coincides with the horizontal and vertical pixels of the detector.

[0032] Specifically, if the slit is tilted, such as Figure 2 As shown, the vertical pixels of the slit and the detector will not coincide. If there is a lateral displacement deviation between the slit and the detector, such as Figure 3 As shown, the vertical pixel of the slit and the detector will not overlap. Therefore, in order to ensure the imaging quality, the processing module 4 can adjust the tilt angle of the tilt adjustment platform 204 according to the tilt angle of the slit, so that the tilt angle of the slit and the detector are the same. By adjusting the lateral displacement of the tilt adjustment platform 204, the slit and the detector are aligned horizontally, thereby making the horizontal and vertical pixels of the slit and the detector overlap, thereby improving the imaging quality. The imaging during the adjustment process of the light emitting module by the processing module 4 can be seen in Figure 4 ,Depend on Figure 4 It can be seen that after adjustment, the slit and the horizontal and vertical pixels of the detector coincide with each other, which greatly improves the imaging quality and thus improves the accuracy of subsequent optical transfer function calculations.

[0033] In another embodiment of the present invention, Figure 1 As shown, the above-mentioned automatic optical transfer function test system can also include: an adjustment platform 6, on which the optical system 5 to be tested is fixed, and the adjustment platform 6 is used to adjust the azimuth and pitch angles of the optical system to be tested; the processing module 4 is also used to adjust the azimuth and pitch angles of the optical system to be tested by controlling the adjustment platform 6 to set different fields of view and calculate the optical transfer functions of the on-axis and off-axis fields of view of the optical system to be tested.

[0034] Specifically, if the optical transfer functions of different fields of view of the measured optical system are to be calculated, the azimuth and elevation angles of the measured optical system can be adjusted by controlling the adjustment platform 6 to calculate the optical transfer functions of the on-axis and off-axis fields of view of the measured optical system.

[0035] The entire optical transfer function automatic test system mentioned above can be set up on an optical platform to improve the accuracy of the test.

[0036] In order to make those skilled in the art understand the present invention more clearly, the following Figure 5 The flowchart of FIG. 1 is used to describe the working process of the optical transfer function automatic testing system of the present invention. Figure 5 As shown, the execution subject of the system is a processing module, which can execute the following workflow to achieve the purpose of the present invention:

[0037] S1, acquiring imaging data of the detector, and automatically focusing the detector according to the imaging situation to make the imaging image clear.

[0038] S2, switching the slit angular resolution of the slit plate by controlling the graticule switching device so that the slit size corresponds to the angular resolution of the optical system under test.

[0039] S3, automatically identifying the slit tilt angle of the slit plate, adjusting the tilt angle of the tilt adjustment platform according to the slit tilt angle, and adjusting the lateral displacement of the tilt adjustment platform so that the slit coincides with the horizontal and vertical pixels of the detector.

[0040] S4, automatically collects imaging data of the detector, calculates the optical transfer function based on the imaging data, and displays the calculation results.

[0041] In summary, the optical transfer function automatic test system according to the embodiment of the present invention can perform automatic testing of optical transfer functions quickly, accurately, and with high repeatability, and the entire system is integrated using universal equipment, which is convenient for test construction and saves costs.

[0042] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. "Multiple" means two or more, unless otherwise clearly and specifically defined.

[0043] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0044] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0045] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0046] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0047] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0048] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0049] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc.

[0050] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An automatic optical transfer function test system, characterized in that: include: Detector, light emitting module, collimator and processing module; One side of the optical system under test is aligned with the light outlet of the collimator, and the detector is arranged on the other side of the optical system under test. The outgoing light of the light emitting module passes through the collimator to form parallel light and irradiates one side of the optical system under test, and the outgoing light on the other side of the optical system under test is received by the detector and imaged. The processing module is used to obtain the imaging data of the detector, automatically focus the detector according to the imaging situation to make the imaging image clear, and adjust the position of the light emitting module to align with the detector, automatically collect the imaging data of the detector, calculate the optical transfer function according to the imaging data, and display the calculation results.

2. The optical transfer function automatic testing system according to claim 1, characterized in that: The optical transmission module comprises: light source; A slit plate, arranged directly in front of the light source; A graticule switching device, the graticule switching device is used to switch the slit angle resolution of the slit plate; The tilt adjustment platform is used to adjust the tilt angle of the slit of the slit plate.

3. The optical transfer function automatic testing system according to claim 2, characterized in that: The processing module is specifically used for: The slit angular resolution of the slit plate is switched by controlling the graticule switching device so that the slit size corresponds to the angular resolution of the optical system under test; The slit tilt angle of the slit plate is automatically identified, the tilt angle of the tilt adjustment platform is adjusted according to the slit tilt angle, and the lateral displacement of the tilt adjustment platform is adjusted so that the slit coincides with the horizontal and vertical direction pixels of the detector.

4. The optical transfer function automatic testing system according to claim 1, characterized in that: Also includes: An adjustment platform, on which the optical system to be measured is fixed, and the adjustment platform is used to adjust the azimuth and elevation angles of the optical system to be measured; The processing module is also used to adjust the azimuth and elevation angles of the optical system under test by controlling the adjustment platform to set different fields of view and calculate the optical transfer functions of the on-axis and off-axis fields of view of the optical system under test.

5. The optical transfer function automatic testing system according to claim 1, characterized in that: The processing module specifically calculates the optical transfer function according to the following formula: Where MTF stands for the optical transfer function, DN max Represents the bright fringe pixel signal, DN min represents the dark fringe pixel signal, and DN represents the background noise.

6. The optical transfer function automatic testing system according to claim 1, characterized in that: The whole system is mounted on an optical platform.

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