Wavefront sensor, wavefront measuring method, wavefront measuring system and electronic equipment

Abstract

The invention provides a wavefront sensor, a wavefront measuring method, a wavefront measuring system and electronic equipment, and relates to the technical field of optical measurement, the wavefront sensor comprises a semi-reflecting and semi-transmitting mirror, a first microlens array, a second microlens array, a first detector and a second detector; the half-reflecting and half-transmitting mirror is used for separating incident wavefront to be measured into reflected wavefront and transmitted wavefront; the first micro lens array is perpendicular to the half-reflection and half-transmission mirror reflection light path and is arranged on the focal plane of the half-reflection and half-transmission mirror reflection light path. The second microlens array is perpendicular to the transmission light path of the half-reflecting and half-transmitting mirror and is arranged on the focal plane of the transmission light path of the half-reflecting and half-transmitting mirror. According to the wavefront sensor, the wavefront measurement method, the wavefront measurement system and the electronic equipment provided by the invention, the measurement capability of the wavefront sensor on high-curvature and large-amplitude wavefront distortion can be remarkably improved on the basis of not reducing the sensitivity of the wavefront sensor.

Description

Technical Field

[0001] The present invention relates to the field of optical measurement technology, and in particular to a wavefront sensor, a wavefront measurement method, a system and an electronic device. Background Art

[0002] A wavefront sensor, also known as a wavefront detector or wavefront analyzer, is a device used to accurately measure and analyze optical wavefronts.

[0003] Traditional wavefront sensors in related technologies can split the incident wavefront into multiple sub-wavefronts through a microlens array and form a light spot on the detector. By obtaining the offset of the light spot, the wavefront morphology is reconstructed to obtain complete wavefront information.

[0004] However, in the related art, conventional wavefront sensors have defects such as complex hardware operation or slow subsequent calculation speed when measuring wavefronts with high curvature or large dynamic range, which limit the application and performance of conventional wavefront sensors in wavefront measurement with high curvature or large dynamic range. Therefore, how to improve the speed of subsequent calculation without increasing the complexity of the hardware operation of the wavefront sensor, thereby improving the application and performance of the wavefront sensor in measuring wavefronts with high curvature or large dynamic range. Summary of the invention

[0005] The present invention provides a wavefront sensor, a wavefront measurement method, a system and an electronic device, which are used to solve the defects of traditional wavefront sensors in the prior art that have complex hardware structure and slow subsequent calculation speed when measuring wavefronts with high curvature or a large dynamic range, and improve the speed of subsequent calculation without increasing the hardware operation complexity of the wavefront sensor, thereby improving the application and performance of the wavefront sensor when measuring wavefronts with high curvature or a large dynamic range.

[0006] The present invention provides a wavefront sensor, comprising: a semi-reflective and semi-transmissive mirror, a first microlens array, a second microlens array, a first detector and a second detector; the first microlens array and the second microlens array are the same microlens array; the first detector and the second detector are the same detector; The semi-reflective and semi-transmissive mirror is composed of a plurality of reflective parts and a plurality of transmissive parts, the reflective parts and the transmissive parts are both rectangular and have equal areas, the reflective parts and the transmissive parts are arranged alternately, and the semi-reflective and semi-transmissive mirror is used to separate the incident wavefront to be measured into a reflected wavefront and a transmitted wavefront; The first microlens array is perpendicular to the reflection light path of the semi-reflective and semi-transmissive mirror and is arranged on the focal plane of the reflection light path of the semi-reflective and semi-transmissive mirror; The second microlens array is perpendicular to the transmission light path of the semi-reflective and semi-transmissive mirror and is arranged on the focal plane of the transmission light path of the semi-reflective and semi-transmissive mirror; The first detector is coaxially arranged with the first microlens array, and the first detector is used to record a first light spot distribution diagram formed after the reflected wavefront passes through the first microlens array; The second detector is coaxially arranged with the second microlens array, and is used for recording a second light spot distribution diagram formed after the transmission wavefront passes through the second microlens array.

[0007] A wavefront sensor provided according to the present invention also includes: a front optical lens; the front optical lens includes at least one of a beam reducer, a beam expander and a collimator arranged along the incident light path of the wavefront to be measured; the front optical lens is coaxially arranged with the semi-reflective and semi-transmissive mirror, and the front optical lens and the semi-reflective and semi-transmissive mirror are arranged in sequence along the incident light path of the wavefront to be measured.

[0008] According to a wavefront sensor provided by the present invention, the front optical lens further includes: a filter arranged along the incident light path of the wavefront to be measured.

[0009] According to a wavefront sensor provided by the present invention, both the first detector and the second detector are high-speed charge coupled device (CCD) detectors or complementary metal oxide semiconductor (CMOS) detectors.

[0010] The present invention also provides a wavefront measurement method, comprising: obtaining a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on any of the wavefront sensors described above; based on the first light spot distribution map and the second light spot distribution map, reconstructing the wavefront to be measured to obtain phase information of the wavefront to be measured.

[0011] According to a wavefront measurement method provided by the present invention, reconstructing the wavefront to be measured based on the first light spot distribution map and the second light spot distribution map to obtain the phase information of the wavefront to be measured includes: Record the light spot positions in the first light spot distribution map at a type-one position in a blank matrix, and record the light spot positions in the second light spot distribution map at a type-two position in the blank matrix, to obtain a target matrix, wherein each of the type-one position and each of the type-two positions in the blank matrix is ​​determined based on the arrangement of each reflecting part and each transmitting part in the semi-reflective and semi-transmissive mirror in the wavefront sensor, wherein the type-one position corresponds to the reflecting part, and the type-two position corresponds to the transmitting part; Based on the target matrix, the wavefront to be measured is reconstructed to obtain phase information of the wavefront to be measured.

[0012] According to a wavefront measurement method provided by the present invention, the spot positions in the first spot distribution map are recorded at a type of position in a blank matrix, and the spot positions in the second spot distribution map are recorded at a type of position in the blank matrix to obtain a target matrix, including: Performing grid division on the first spot distribution map and the second spot distribution map respectively, generating a target number of grids of the same size in the first spot distribution map, and generating a target number of grids of the same size in the second spot distribution map, wherein the target number is the total number of each of the first type of positions and each of the second type of positions in the blank matrix; Based on the distribution of each of the first type of positions in the blank matrix, determine the grid corresponding to each of the first type of positions in the first light spot distribution map; based on the distribution of each of the second type of positions in the blank matrix, determine the grid corresponding to each of the second type of positions in the second light spot distribution map; For each grid corresponding to the first type of position, a right triangle is generated in a direction away from the grid corresponding to the first type of position with each side of the grid corresponding to the first type of position as a hypotenuse, so as to obtain each right triangle corresponding to the first type of position; for each grid corresponding to the second type of position, a right triangle is generated in a direction away from the grid corresponding to the second type of position with each side of the grid corresponding to the second type of position as a hypotenuse, so as to obtain each right triangle corresponding to the second type of position; The grids corresponding to each type of position in the first light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix, and the grids corresponding to each type of position in the second light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix.

[0013] According to a wavefront measurement method provided by the present invention, before obtaining the first light spot distribution map and the second light spot distribution map, the method further includes: The wavefront sensor is calibrated based on a standard parallel light source, and a coaxial relationship between components in the wavefront sensor is established.

[0014] The present invention also provides a wavefront measurement system, comprising: a wavefront sensor as described above and an electronic device; the electronic device is electrically connected to a first detector and a second detector in the wavefront sensor respectively; The electronic device is used to reconstruct the wavefront to be measured based on the first light spot distribution map and the second light spot distribution map to obtain phase information of the wavefront to be measured.

[0015] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, any of the wavefront measurement methods described above is implemented.

[0016] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the wavefront measurement method as described above is implemented.

[0017] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the wavefront measurement method described above is implemented.

[0018] The present invention provides a wavefront sensor, a wavefront measurement method, a system and an electronic device. The wavefront sensor includes a semi-reflective and semi-transmissive mirror, a first microlens array, a second microlens array, a first detector and a second detector. The semi-reflective and semi-transmissive mirror is used to separate the incident wavefront to be measured into a reflected wavefront and a transmitted wavefront, and then two groups of completely identical microlens arrays and detectors can be used to obtain two light spot distribution diagrams, respectively. Without reducing the sensitivity of the wavefront sensor, the wavefront sensor's measurement capability for high curvature and large-amplitude wavefront distortion is significantly improved. By introducing the semi-reflective and semi-transmissive mirror and another group of microlens arrays and detectors, more light spot position information can be obtained, the correspondence between the light spot and the microlens array can be more accurately obtained, the accuracy of the wavefront measurement can be improved, and while improving the dynamic range of the wavefront sensor, excessive hardware complexity can be avoided. The feasibility and cost-effectiveness of the wavefront sensor can be ensured, the real-time wavefront measurement requirements can be met, the application scope of the wavefront sensor can be expanded, and higher optical measurement requirements can be met. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the principle of a Shack-Hartmann wavefront sensor in the related art.

[0021] Figure 2 It is a schematic diagram of the structure of the wavefront sensor provided by the present invention.

[0022] Figure 3 It is a schematic diagram of the structure of a semi-reflective and semi-transmissive mirror in a wavefront sensor provided by the present invention.

[0023] Figure 4 A schematic diagram of a grid corresponding to a type of position in the first spot distribution diagram in the wavefront measurement method provided by the present invention.

[0024] Figure 5 It is a flow chart of the wavefront measurement method provided by the present invention.

[0025] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are 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.

[0027] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the description of the present application, the terms "first", "second", etc. are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are usually a class, and the number of objects is not limited. For example, the first object can be one or more. In addition, in the description of the present application, "and / or" represents at least one of the connected objects, and the character " / " generally represents that the front and back associated objects are in an "or" relationship.

[0029] It should be noted that the Shack-Hartmann Wavefront Sensor (SHWFS for short) is a wavefront sensor commonly used in related technologies. Figure 1 FIG. 1 is a schematic diagram of the principle of a Shack-Hartmann wavefront sensor in the related art. Figure 1As shown in the figure, the Shack-Hartmann wavefront sensor includes a microlens array and a detector. The microlens array is an array composed of many small lenses (sub-apertures) arranged regularly. When the wavefront to be measured is incident on the microlens array, the microlens array can divide the wavefront to be measured into multiple sub-wavefronts. The detector is located in the focal plane of the microlens array and can be used to record the light spot formed by focusing each sub-aperture.

[0030] When the wavefront to be measured is distorted (such as caused by optical aberration or medium disturbance), the position of the light spot in the detector image will deviate from its ideal position (reference datum). By obtaining the offset of any light spot in the detector image, the local slope of the sub-aperture corresponding to the above light spot can be calculated. By integrating the local slopes of all sub-apertures, the phase distribution of the wavefront to be measured can be reconstructed.

[0031] In the related art, the offset of the light spot can be obtained by a centroid estimation method. Specifically, the centroid estimation method can determine the position of the centroid of each light spot image in the detector image according to the range corresponding to each sub-aperture of the detector, and then the offset of the light spot can be obtained based on the position of the centroid of each light spot image.

[0032] In order to improve the adaptability of the Shack-Hartmann wavefront sensor to wavefront measurements with high curvature or large dynamic range, there are several solutions in the relevant technology: First, use a spatial light modulator array to open and close the sub-apertures, open only one sub-aperture at a time, then close the sub-aperture, and then open the next sub-aperture, detect and record the offset of the light spot, and repeat this operation until all sub-apertures have been opened.

[0033] Second, the offset of the light spot is obtained based on the iterative extrapolation method of the B-Spline function. The algorithm assumes that the nine points in the center of the detector image correspond to the sub-lenses above them. According to the connection pairs of these light spots and sub-lenses, the offset of the light spot is fitted by the B-Spline function, and then the function is extrapolated to the nearest sub-lens that has not yet been connected to give the expected position of the light spot. If a new light spot is close enough to these expected positions, it will be selected and connected, and it will be iterated back and forth until all the light spots are sorted and numbered.

[0034] Third, the offset of the light spot is obtained based on the iterative extrapolation method of Zernike polynomials. The algorithm is initialized starting from nine points in the center of the detector image, and the assigned points are fitted using Zernike polynomials. The positions of the surrounding light spots are extrapolated and predicted using the fitted polynomials, and the light spot closest to the predicted position is assigned to the corresponding lens. This process is repeated until all the light spots are assigned.

[0035] However, in the first solution, the dynamic switching control of the sub-aperture needs to rely on hardware operation, which has a slow processing speed and requires multiple exposures, making it difficult to meet the needs of real-time wavefront measurement. In addition, the introduction of a spatial light modulator increases the complexity and cost of the wavefront sensor and requires precise control and calibration.

[0036] The second solution mentioned above has high requirements on the distribution of the light spot. If the light spot is seriously out of the sub-aperture or the data is missing, the fitting accuracy will be greatly reduced. The iterative process requires multiple calculations, which increases the computational complexity and time cost.

[0037] In the third solution mentioned above, the algorithm depends on the initial spot distribution. If the initial fitting error is large, it may cause the iterative result to deviate. The iterative process requires multiple calculations, which increases the computational complexity and time cost.

[0038] Therefore, the Shack-Hartmann wavefront sensor in the related art has defects such as complex hardware operation or slow subsequent calculation speed when measuring wavefronts with high curvature or large dynamic range. These defects limit the application and performance of the Shack-Hartmann wavefront sensor in wavefront measurement with high curvature or large dynamic range, and it is difficult to meet the real-time wavefront measurement needs.

[0039] In view of this, the present invention provides a wavefront sensor. The wavefront sensor provided by the present invention can significantly improve the dynamic range and measurement speed of the wavefront sensor by introducing a semi-reflective semi-transmissive mirror and two groups of microlens arrays and detectors.

[0040] Combine the following Figure 2-Figure 4 The wavefront sensor provided by the present invention is described.

[0041] Figure 2 Schematic diagram of the structure of the wavefront sensor provided by the present invention. Figure 2 The wavefront sensor provided by the present invention is described. Figure 2 As shown, the wavefront sensor 201 includes: a semi-reflective and semi-transmissive mirror 202, a first microlens array 203, a second microlens array 204, a first detector 205 and a second detector 206; the first microlens array 203 and the second microlens array 204 are the same microlens arrays; the first detector 205 and the second detector 206 are the same detectors.

[0042] The semi-reflective and semi-transmissive mirror 202 is composed of multiple reflective parts and multiple transmissive parts. The reflective parts and the transmissive parts are both rectangular and have equal areas. The reflective parts and the transmissive parts are arranged alternately. The semi-reflective and semi-transmissive mirror 202 is used to separate the incident wavefront to be measured into a reflected wavefront and a transmitted wavefront.

[0043] The first microlens array 203 is perpendicular to the light path reflected by the semi-reflective and semi-transmissive mirror 202 and is disposed on the focal plane of the light path reflected by the semi-reflective and semi-transmissive mirror 202 .

[0044] The second microlens array 204 is perpendicular to the transmission light path of the semi-reflective and semi-transmissive mirror 202 and is disposed on the focal plane of the transmission light path of the semi-reflective and semi-transmissive mirror 202 .

[0045] The first detector 205 is coaxially arranged with the first microlens array 203 , and is used to record a first light spot distribution diagram formed after the reflected wavefront passes through the first microlens array 203 .

[0046] The second detector 206 is coaxially disposed with the second microlens array 204 , and is used for recording a second light spot distribution diagram formed after the transmission wavefront passes through the second microlens array 204 .

[0047] It should be noted that Figure 3 It is a schematic diagram of the structure of a semi-reflective and semi-transmissive mirror in a wavefront sensor provided by the present invention. Figure 3 The black block in the figure represents the reflective portion of the semi-reflective and semi-transmissive mirror 202. Figure 3 The white block in the figure represents the transmissive portion of the semi-reflective and semi-transmissive mirror 202. Figure 3 As shown, unlike the conventional semi-reflective and semi-transmissive mirror 202, the multiple reflective parts and the multiple transmissive parts in the semi-reflective and semi-transmissive mirror in the embodiment of the present invention are arranged in a checkerboard pattern.

[0048] like Figure 2 As shown, when a part of the wavefront to be measured is incident on the reflecting part in the semi-reflective and semi-transmissive mirror 202, the reflecting part can reflect this part of the wavefront to be measured to obtain the reflected wavefront. When another part of the wavefront to be measured is incident on the transmitting part in the semi-reflective and semi-transmissive mirror, the transmitting part can transmit this part of the wavefront to be measured to obtain the transmitted wavefront, thereby realizing the separation of the wavefront to be measured.

[0049] It can be understood that the transmission light path of the semi-reflective and semi-transmissive mirror 202 is the same as the incident light path of the wavefront to be measured, and the reflection light path of the semi-reflective and semi-transmissive mirror 202 is related to the reflection direction of the reflection part.

[0050] Optionally, the reflected light path of the semi-reflective and semi-transmissive mirror is perpendicular to the incident light path of the wavefront to be measured.

[0051] It should be noted that the first microlens array 203 and the second microlens array 204 in the embodiment of the present invention are two completely identical microlens arrays. The first detector 205 and the second detector 206 are two completely identical detectors.

[0052] Optionally, the first microlens array 203 and the second microlens array 204 in the embodiment of the present invention may be the same as the microlens array in the Shack-Hartmann wavefront sensor 201 in the related art. The first detector 205 and the second detector 206 in the embodiment of the present invention may be the same as the detector in the Shack-Hartmann wavefront sensor 201 in the related art.

[0053] It should be noted that the focal lengths of the first microlens array 203 and the second microlens array 204 are related to the sensitivity and the supported dynamic range of the wavefront sensor 201 provided by the present invention. The larger the focal lengths of the first microlens array 203 and the second microlens array 204, the smaller the dynamic range supported by the wavefront sensor 201; the smaller the focal lengths of the first microlens array 203 and the second microlens array 204, the larger the dynamic range supported by the wavefront sensor 201.

[0054] In the embodiment of the present invention, based on the actual situation of the wavefront to be measured, microlens arrays with different focal lengths can be selected as the first microlens array 203 and the second microlens array 204. Under the condition that the dynamic range can be met, a microlens array with a larger focal length is selected as the first microlens array 203 and the second microlens array 204 to improve the sensitivity of the wavefront sensor 201.

[0055] As an optional embodiment, the first detector 205 and the second detector 206 are both high-speed charge coupled device (CCD) detectors or complementary metal oxide semiconductor (CMOS) detectors.

[0056] It should be noted that the high-speed CCD (Charge-Coupled Device) detector is a semiconductor device that converts light signals into electrical signals. It is integrated using a highly sensitive semiconductor material and can generate corresponding charge signals based on the light shining on its surface. When light shines on the photosensitive element of the CCD, a current proportional to the intensity of the light is generated. These analog signals are passed to the storage unit of the next photosensitive element and merged with the signal of that element until a unified output is formed. These signals are then processed by an amplifier to ensure that the signal strength of each pixel is consistent, and then converted into a binary digital image matrix by the analog-to-digital conversion chip.

[0057] CMOS (Complementary Metal Oxide Semiconductor) detectors are a type of integrated circuit. In CMOS image sensors, amplifiers and analog-to-digital conversion logic are integrated on each pixel. When light shines on the photodiode of CMOS, the analog signal generated is first amplified by the amplifier and then directly converted into a digital signal. Each photosensitive element can produce a final digital output, which is combined and directly sent to the digital signal processing (DSP) chip for processing.

[0058] As an optional embodiment, the wavefront sensor 201 further includes: a front optical lens 207. The front optical lens 207 includes at least one of a beam reducer, a beam expander, and a collimator arranged along the incident light path of the wavefront to be measured; the front optical lens 207 is coaxially arranged with the semi-reflective and semi-transmissive mirror 202, and the front optical lens 207 and the semi-reflective and semi-transmissive mirror are arranged in sequence along the incident light path of the wavefront to be measured.

[0059] Specifically, the front optical lens 207 in the embodiment of the present invention can be used to image the wavefront pupil to be measured onto the plane where the semi-reflective and semi-mirror lens is located, thereby ensuring the accuracy of the wavefront measurement.

[0060] It should be noted that in the embodiment of the present invention, at least one of a beam reducer, a beam expander and a collimator can be selected as the front optical lens 207 based on the actual situation of the wavefront to be measured and the sizes of the first microlens array 203 and the second microlens array 204.

[0061] It should be noted that in the embodiment of the present invention, at least one of the beam reducer, beam expander and collimator is arranged along the incident light path of the wavefront to be measured, which means that the incident light path of the wavefront to be measured passes through the center point of at least one of the beam reducer, beam expander and collimator.

[0062] Among them, the beam reducer can be used to reduce the beam diameter. The beam expander can be used to expand the beam diameter. The collimator can be used to convert the divergent or converging beam into parallel light (collimated light), ensuring that the spot displacement is only caused by wavefront distortion, rather than the error in the beam propagation direction.

[0063] As an optional embodiment, the front optical lens 207 further includes: a filter arranged along the incident light path of the wavefront to be measured.

[0064] Specifically, the front optical lens 207 in the embodiment of the present invention may further include a filter arranged along the incident light path of the wavefront to be measured, and the filter may be used to select light of a specific wavelength to reduce the influence of stray light on the wavefront measurement.

[0065] It can be understood that based on the first spot distribution diagram formed after the reflected wavefront recorded by the first detector 205 passes through the first microlens array 203 and the second spot distribution diagram formed after the transmitted wavefront recorded by the second detector 206 passes through the second microlens array 204, the wavefront to be measured can be reconstructed through data calculation, mathematical statistics or deep learning technology to obtain the phase information of the wavefront to be measured.

[0066] Specifically, the first spot distribution map and the second spot distribution map are gridded respectively, a target number of grids of the same size are generated in the first spot distribution map, and a target number of grids of the same size are generated in the second spot distribution map, where the target number is the total number of each first-class position and each second-class position in the blank matrix.

[0067] Each type I position and each type II position in the blank matrix is ​​determined based on the arrangement of each reflective part and each transmissive part in the semi-reflective and semi-transmissive mirror 202 in the wavefront sensor 201. The type I position corresponds to the reflective part, and the type II position corresponds to the transmissive part.

[0068] The blank matrix in the embodiment of the present invention can be expressed by the following formula:

[0069] Blank Matrix For a type of position, since the reflective parts and the transmissive parts in the semi-reflective and semi-transmissive mirror 202 in the wavefront sensor 201 are alternately arranged in the horizontal direction and the vertical direction, any two type of positions in the blank matrix are not adjacent.

[0070] Accordingly, in the blank matrix are two-category positions, and any two two-category positions in the blank matrix are not adjacent.

[0071] Based on the distribution of each type of position in the blank matrix, the grid corresponding to each type of position is determined in the first spot distribution map, and based on the distribution of each type of position in the blank matrix, the grid corresponding to each type of position is determined in the second spot distribution map.

[0072] Figure 4 Schematic diagram of a grid corresponding to a type of position in the first spot distribution diagram in the wavefront measurement method provided by the present invention. Figure 4 As shown, a type of position The gray square where it is located is a type of position in the first spot distribution diagram The corresponding grid.

[0073] For the grid corresponding to each type of position, each side of the grid corresponding to each type of position is used as the hypotenuse, and a right triangle is generated in the direction away from the grid corresponding to each type of position to obtain the right triangles corresponding to each type of position. For the grid corresponding to each type of position, each side of the grid corresponding to each type of position is used as the hypotenuse, and a right triangle is generated in the direction away from the grid corresponding to each type of position to obtain the right triangles corresponding to each type of position.

[0074] Specifically, Figure 4 As shown, a type of position The black right triangles around the corresponding grid are a type of position The corresponding right triangle , right triangle , right triangle and a right triangle .

[0075] The grids corresponding to each type of position in the first light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix, and the grids corresponding to each type of position in the second light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix.

[0076] Specifically, Figure 4 As shown, a type of position The corresponding grid and a type of position The corresponding right triangle , right triangle , right triangle and a right triangle The location information of the light spot in the area is written into a type of position in the blank matrix Place.

[0077] It should be noted that the dynamic range of the Shack-Hartmann wavefront sensor 201 in the related art is the gray area in the first light spot distribution diagram. When the light spot is not in the gray area, it is impossible to determine which sub-aperture in the microlens array the light spot corresponds to.

[0078] Since the wavefront sensor 201 in the embodiment of the present invention is provided with a semi-reflective and semi-transmissive mirror 202, there are no light spots transmitted through the first microlens array 203 in the grids on both sides of the grid corresponding to the first type of position in the first light spot distribution diagram, and there are no light spots transmitted through the second microlens array 204 in the grids on both sides of the grid corresponding to the second type of position in the second light spot distribution diagram. The light spots in the area where the right-angled triangles corresponding to any one type of position in the first light spot distribution diagram are located can be determined as belonging to the above-mentioned first type of position, and the light spots in the area where the right-angled triangles corresponding to any two types of positions in the second light spot distribution diagram are located can be determined as belonging to the above-mentioned two types of positions, thereby improving the dynamic range of wavefront measurement.

[0079] The spacing between the microlens units in the first microlens array 203 and the second microlens array 204 is x In the case of , the side length of the grid in the first spot distribution diagram and the second spot distribution diagram is x The dynamic range of the Shack-Hartmann wavefront sensor 201 in the related art is x The dynamic range of the wavefront sensor 201 in the embodiment of the present invention is extended to The dynamic range area is doubled.

[0080] After obtaining the above-mentioned target matrix, the wavefront slope matrix of each light spot in the first light spot distribution map and the wavefront slope matrix of each light spot in the second light spot distribution map can be calculated respectively based on the above-mentioned target matrix, the first light spot distribution map and the second light spot distribution map, and then the above-mentioned two wavefront slope matrices can be merged to obtain a complete wavefront slope matrix.

[0081] Based on the above complete wavefront slope matrix, the wavefront to be measured can be reconstructed to obtain the phase information of the wavefront to be measured.

[0082] The wavefront sensor in the embodiment of the present invention includes a semi-reflective and semi-transmissive mirror, a first microlens array, a second microlens array, a first detector and a second detector. The incident wavefront to be measured is separated into a reflected wavefront and a transmitted wavefront by the semi-reflective and semi-transmissive mirror, and then two light spot distribution diagrams can be obtained respectively through two groups of completely identical microlens arrays and detectors. The wavefront sensor's measurement capability for high curvature and large-amplitude wavefront distortion can be significantly improved without reducing the sensitivity of the wavefront sensor. By introducing a semi-reflective and semi-transmissive mirror and another group of microlens arrays and detectors, more light spot position information can be obtained, the correspondence between the light spot and the microlens array can be more accurately obtained, the accuracy of the wavefront measurement can be improved, and while improving the dynamic range of the wavefront sensor, excessive hardware complexity can be avoided. The feasibility and cost-effectiveness of the wavefront sensor can be ensured, the real-time wavefront measurement requirements can be met, the application scope of the wavefront sensor can be expanded, and higher optical measurement requirements can be met.

[0083] Figure 5 2 is a flow chart of the wavefront measurement method provided by the present invention. The wavefront measurement method provided by the present invention is implemented based on the above-mentioned wavefront sensor 201. Figure 5 As shown, the method includes the following: Step 501, acquiring a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on the wavefront sensor 201 as described above.

[0084] It should be noted that the executor of the embodiment of the present invention is a wavefront measurement device, and the wavefront measurement device can be configured in electronic devices such as computers or servers.

[0085] It should be noted that the first light spot distribution map and the second light spot distribution map in the embodiment of the present invention can be generated based on the wavefront sensor 201 mentioned above, and the specific generation method of the first light spot distribution map and the second light spot distribution map in the embodiment of the present invention will not be repeated.

[0086] In the embodiment of the present invention, the first light spot distribution map and the second light spot distribution map can be acquired by exchanging control instructions.

[0087] Step 502: reconstruct the wavefront to be measured based on the first light spot distribution map and the second light spot distribution map to obtain phase information of the wavefront to be measured.

[0088] Specifically, after obtaining the first light spot distribution map and the second light spot distribution map, the wavefront to be measured can be reconstructed based on the first light spot distribution map and the second light spot distribution map through numerical calculation, mathematical statistics or deep learning technology to obtain the phase information of the wavefront to be measured.

[0089] As an optional embodiment, based on the first light spot distribution map and the second light spot distribution map, the wavefront to be measured is reconstructed to obtain the phase information of the wavefront to be measured, including: recording the light spot positions in the first light spot distribution map at a type of position in a blank matrix, and recording the light spot positions in the second light spot distribution map at a type of position in the blank matrix to obtain a target matrix, wherein each type of position and each type of position in the blank matrix is ​​determined based on the arrangement of each reflective part and each transmissive part in the semi-reflective and semi-transmissive mirror 202 in the wavefront sensor 201, and the type of position corresponds to the reflective part, and the type of position corresponds to the transmissive part.

[0090] Specifically, the blank matrix in the embodiment of the present invention can be expressed by the following formula:

[0091] Blank Matrix For a type of position, since the reflective parts and the transmissive parts in the semi-reflective and semi-transmissive mirror 202 in the wavefront sensor 201 are alternately arranged in the horizontal direction and the vertical direction, any two type of positions in the blank matrix are not adjacent.

[0092] Accordingly, in the blank matrix are two-category positions, and any two two-category positions in the blank matrix are not adjacent.

[0093] After acquiring the first light spot distribution map, a type of position corresponding to each light spot can be determined based on the distribution of the light spots in the first light spot distribution map, and then the position of each light spot in the first light spot distribution map can be recorded at a type of position corresponding to each light spot in the blank matrix.

[0094] Similarly, after obtaining the second light spot distribution map, the second type of position corresponding to each light spot can be determined based on the distribution of the light spots in the second light spot distribution map, and then the position of each light spot in the second light spot distribution map can be recorded at the second type of position corresponding to each light spot in the blank matrix.

[0095] As an optional embodiment, the spot positions in the first spot distribution map are recorded at the first type of positions in the blank matrix, and the spot positions in the second spot distribution map are recorded at the second type of positions in the blank matrix to obtain a target matrix, including: gridding the first spot distribution map and the second spot distribution map respectively, generating a target number of grids of the same size in the first spot distribution map, and generating a target number of grids of the same size in the second spot distribution map, where the target number is the total number of each type of position and each type of position in the blank matrix.

[0096] Based on the distribution of each type of position in the blank matrix, the grid corresponding to each type of position is determined in the first spot distribution map, and based on the distribution of each type of position in the blank matrix, the grid corresponding to each type of position is determined in the second spot distribution map.

[0097] like Figure 4 As shown, a type of position The gray square where it is located is a type of position in the first spot distribution diagram The corresponding grid.

[0098] For the grid corresponding to each type of position, each side of the grid corresponding to each type of position is used as the hypotenuse, and a right triangle is generated in the direction away from the grid corresponding to each type of position to obtain the right triangles corresponding to each type of position. For the grid corresponding to each type of position, each side of the grid corresponding to each type of position is used as the hypotenuse, and a right triangle is generated in the direction away from the grid corresponding to each type of position to obtain the right triangles corresponding to each type of position.

[0099] Specifically, Figure 4 As shown, a type of position The black right triangles around the corresponding grid are a type of position The corresponding right triangle , right triangle , right triangle and a right triangle .

[0100] The grids corresponding to each type of position in the first light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix, and the grids corresponding to each type of position in the second light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix.

[0101] Specifically, Figure 4 As shown, a type of position The corresponding grid and a type of position The corresponding right triangle , right triangle , right triangle and a right triangle The location information of the light spot in the area is written into a type of position in the blank matrix Place.

[0102] It should be noted that the dynamic range of the Shack-Hartmann wavefront sensor 201 in the related art is the gray area in the first light spot distribution diagram. When the light spot is not in the gray area, it is impossible to determine which sub-aperture in the microlens array the light spot corresponds to.

[0103] Since the wavefront sensor 201 in the embodiment of the present invention is provided with a semi-reflective and semi-transmissive mirror 202, there are no light spots transmitted through the first microlens array 203 in the grids on both sides of the grid corresponding to the first type of position in the first light spot distribution diagram, and there are no light spots transmitted through the second microlens array 204 in the grids on both sides of the grid corresponding to the second type of position in the second light spot distribution diagram. The light spots in the area where the right-angled triangles corresponding to any one type of position in the first light spot distribution diagram are located can be determined as belonging to the above-mentioned first type of position, and the light spots in the area where the right-angled triangles corresponding to any two types of positions in the second light spot distribution diagram are located can be determined as belonging to the above-mentioned two types of positions, thereby improving the dynamic range of wavefront measurement.

[0104] When the spacing between the microlens units in the first microlens array 203 and the second microlens array 204 is x, the side length of the grid in the first light spot distribution diagram and the second light spot distribution diagram is x. The dynamic range of the Shack-Hartmann wavefront sensor 201 in the related art is a square with a side length of x, while the dynamic range of the wavefront sensor 201 in the embodiment of the present invention is extended to The dynamic range area is doubled.

[0105] Based on the target matrix, the wavefront to be measured is reconstructed to obtain the phase information of the wavefront to be measured.

[0106] Specifically, after obtaining the above-mentioned target matrix, the wavefront slope matrix of each light spot in the first light spot distribution map and the wavefront slope matrix of each light spot in the second light spot distribution map can be calculated respectively based on the above-mentioned target matrix, the first light spot distribution map and the second light spot distribution map, and then the above-mentioned two wavefront slope matrices can be merged to obtain a complete wavefront slope matrix.

[0107] Based on the above complete wavefront slope matrix, the wavefront to be measured can be reconstructed to obtain the phase information of the wavefront to be measured.

[0108] As an optional embodiment, before acquiring the first light spot distribution map and the second light spot distribution map, the method further includes: calibrating the wavefront sensor 201 based on a standard parallel light source to establish a coaxial relationship between components in the wavefront sensor 201 .

[0109] Based on the contents of the above embodiments, a wavefront measurement system includes: the wavefront sensor 201 as above and an electronic device; the electronic device is electrically connected to the first detector 205 and the second detector 206 in the wavefront sensor 201 respectively.

[0110] The electronic device is used to obtain the first spot distribution map recorded by the first detector 205 and the second spot distribution map recorded by the second eye side wall, and then reconstruct the wavefront to be measured based on the first spot distribution map and the second spot distribution map to obtain the phase information of the wavefront to be measured.

[0111] The wavefront measurement system provided by the present invention, through a semi-reflective and semi-transmissive mirror and an optimized data processing flow, significantly improves the measurement capability of high curvature and large-amplitude wavefront distortion without significantly increasing the complexity of the system, improves the accuracy of wavefront measurement, and can obtain the distribution image of all light spots in a single exposure, and can complete wavefront reconstruction without multiple exposures and complicated algorithms, which can save a lot of measurement time, improve the efficiency of wavefront measurement, meet the real-time wavefront measurement needs, expand the application range of wavefront sensors, ensure the feasibility and cost-effectiveness of wavefront measurement, and meet higher requirements for optical measurement.

[0112] Figure 6 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other through the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute the wavefront measurement method, which includes: obtaining a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on the above-mentioned wavefront sensor; based on the first light spot distribution map and the second light spot distribution map, reconstructing the wavefront to be measured to obtain the phase information of the wavefront to be measured.

[0113] In addition, the logic instructions in the above-mentioned memory 630 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0114] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the wavefront measurement method provided by the above-mentioned methods, and the method includes: obtaining a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on the above-mentioned wavefront sensor; based on the first light spot distribution map and the second light spot distribution map, reconstructing the wavefront to be measured to obtain the phase information of the wavefront to be measured.

[0115] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the wavefront measurement method provided by the above-mentioned methods. The method includes: obtaining a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on the above-mentioned wavefront sensor; based on the first light spot distribution map and the second light spot distribution map, reconstructing the wavefront to be measured to obtain the phase information of the wavefront to be measured.

[0116] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0117] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wavefront sensor, characterized in that: include: A semi-reflective and semi-transmissive mirror, a first microlens array, a second microlens array, a first detector and a second detector; The first microlens array and the second microlens array are the same microlens array; the first detector and the second detector are the same detector; The semi-reflective and semi-transmissive mirror is composed of a plurality of reflective parts and a plurality of transmissive parts, the reflective parts and the transmissive parts are both rectangular and have equal areas, the reflective parts and the transmissive parts are arranged alternately, and the semi-reflective and semi-transmissive mirror is used to separate the incident wavefront to be measured into a reflected wavefront and a transmitted wavefront; The first microlens array is perpendicular to the reflection light path of the semi-reflective and semi-transmissive mirror and is arranged on the focal plane of the reflection light path of the semi-reflective and semi-transmissive mirror; The second microlens array is perpendicular to the transmission light path of the semi-reflective and semi-transmissive mirror and is arranged on the focal plane of the transmission light path of the semi-reflective and semi-transmissive mirror; The first detector is coaxially arranged with the first microlens array, and the first detector is used to record a first light spot distribution diagram formed after the reflected wavefront passes through the first microlens array; The second detector is coaxially arranged with the second microlens array, and is used for recording a second light spot distribution diagram formed after the transmission wavefront passes through the second microlens array.

2. The wavefront sensor according to claim 1, characterized in that: Also includes: A front optical lens; the front optical lens comprises at least one of a beam reducer, a beam expander and a collimator arranged along the incident light path of the wavefront to be measured; The front optical lens is coaxially arranged with the semi-reflective and semi-transmissive mirror, and the front optical lens and the semi-reflective and semi-transmissive mirror are arranged in sequence along the incident light path of the wavefront to be measured.

3. The wavefront sensor according to claim 2, characterized in that: The front optical lens further includes: a filter arranged along the incident light path of the wavefront to be measured.

4. The wavefront sensor according to any one of claims 1 to 3, characterized in that: The first detector and the second detector are both high-speed charge-coupled device (CCD) detectors or complementary metal oxide semiconductor (CMOS) detectors.

5. A wavefront measurement method, characterized in that: include: Acquire a first light spot distribution map and a second light spot distribution map, wherein the first light spot distribution map and the second light spot distribution map are generated based on the wavefront sensor according to any one of claims 1 to 4; The wavefront to be measured is reconstructed based on the first light spot distribution map and the second light spot distribution map to obtain phase information of the wavefront to be measured.

6. The wavefront measurement method according to claim 5, characterized in that: The reconstructing the wavefront to be measured based on the first light spot distribution map and the second light spot distribution map to obtain the phase information of the wavefront to be measured includes: Record the light spot positions in the first light spot distribution map at a type-one position in a blank matrix, and record the light spot positions in the second light spot distribution map at a type-two position in the blank matrix, to obtain a target matrix, wherein each of the type-one position and each of the type-two positions in the blank matrix is ​​determined based on the arrangement of each reflecting part and each transmitting part in the semi-reflective and semi-transmissive mirror in the wavefront sensor, wherein the type-one position corresponds to the reflecting part, and the type-two position corresponds to the transmitting part; Based on the target matrix, the wavefront to be measured is reconstructed to obtain phase information of the wavefront to be measured.

7. The wavefront measurement method according to claim 6, characterized in that: The step of recording the light spot positions in the first light spot distribution map at a first type of position in a blank matrix and recording the light spot positions in the second light spot distribution map at a second type of position in the blank matrix to obtain a target matrix comprises: Performing grid division on the first spot distribution map and the second spot distribution map respectively, generating a target number of grids of the same size in the first spot distribution map, and generating a target number of grids of the same size in the second spot distribution map, wherein the target number is the total number of each of the first type of positions and each of the second type of positions in the blank matrix; Based on the distribution of each of the first type of positions in the blank matrix, determine the grid corresponding to each of the first type of positions in the first light spot distribution map; based on the distribution of each of the second type of positions in the blank matrix, determine the grid corresponding to each of the second type of positions in the second light spot distribution map; For each grid corresponding to the first type of position, a right triangle is generated in a direction away from the grid corresponding to the first type of position with each side of the grid corresponding to the first type of position as a hypotenuse, so as to obtain each right triangle corresponding to the first type of position; for each grid corresponding to the second type of position, a right triangle is generated in a direction away from the grid corresponding to the second type of position with each side of the grid corresponding to the second type of position as a hypotenuse, so as to obtain each right triangle corresponding to the second type of position; The grids corresponding to each type of position in the first light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix, and the grids corresponding to each type of position in the second light spot distribution diagram and the position information of the light spots in the area where each right triangle is located are written into each type of position in the blank matrix.

8. The wavefront measurement method according to any one of claims 5 to 7, characterized in that: Before acquiring the first light spot distribution map and the second light spot distribution map, the method further includes: The wavefront sensor is calibrated based on a standard parallel light source, and a coaxial relationship between components in the wavefront sensor is established.

9. A wavefront measurement system, characterized in that: include: The wavefront sensor and electronic device according to any one of claims 1 to 4; the electronic device is electrically connected to the first detector and the second detector in the wavefront sensor respectively; The electronic device is used to reconstruct the wavefront to be measured based on the first light spot distribution map and the second light spot distribution map to obtain phase information of the wavefront to be measured.

10. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the wavefront measurement method according to any one of claims 5 to 8 is implemented.

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