Gray scale writing method and device of microlens, computer device and storage medium

Abstract

The application relates to a gray scale writing method and device, computer equipment and a storage medium. The incident light spot of a grating light valve is determined according to a laser beam emitted by a laser light source; the incident light spot is phase modulated by a subunit of the grating light valve to determine a first-order diffraction light field of the subunit; a writing line light field is determined according to the first-order diffraction light field of the subunit; the writing line light field is rotated by a dove prism to determine a rotating light field; the target light intensity distribution gradient of the writing line light field is determined according to the curved surface structure of a microlens; and the microlens is gray scale written according to the rotating light field, the writing line light field and the target light intensity distribution gradient. The above method can improve the processing efficiency of the microlens and improve the smoothness of the microlens.

Description

Technical Field

[0001] This application relates to the field of photolithography technology, and in particular to a grayscale writing method, apparatus, computer equipment, and storage medium for a microlens. Background Technology

[0002] Microlenses are essentially conventional lenses reduced to the size of hundreds of micrometers, possessing a near-hemispherical curved surface structure. Currently, microlenses are often fabricated using layer-by-layer scanning or exposure with equal laser focal points to obtain a uniform circular structure layer by layer. The bottom layer of the fabricated microlens has the largest diameter, decreasing towards the top, with the smallest diameter at the very top. These fabricated surfaces are then stacked to form the microlens. Therefore, microlenses fabricated using existing methods exhibit noticeable seam marks, resulting in a rough surface that is difficult to achieve high gloss levels, and the fabrication efficiency is relatively low. Therefore, improving the fabrication efficiency and surface finish of microlenses is a problem that needs to be addressed. Summary of the Invention

[0003] Therefore, it is necessary to provide a method, apparatus, computer equipment, and storage medium for grayscale writing of microlenses that can improve the processing efficiency and surface finish of microlenses, thereby addressing the aforementioned technical problems.

[0004] In a first aspect, this application provides a grayscale characterization method for a microlens, the method comprising:

[0005] The incident light spot of the grating light valve is determined based on the laser beam emitted from the laser source;

[0006] The incident light spot is phase-modulated by the grating light valve subunit to determine the first-order diffraction field of the subunit;

[0007] The writing line light field is determined based on the first-order diffraction light field of the sub-unit;

[0008] The rotating light field is determined by rotating the writing line light field through a Dove prism.

[0009] Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the inscribed line light field is determined;

[0010] The microlens is grayscale etched according to the rotating light field, the etched line light field, and the target light intensity distribution gradient.

[0011] In one embodiment, the incident light spot is phase-modulated by a sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit, including:

[0012] The incident light spot is input into the grating light valve, and it is determined whether the sub-unit of the grating light valve is in a diffraction state;

[0013] If so, the grating depth is determined according to the laser wavelength of the laser beam, and the light intensity of the first-order diffracted light of the sub-unit is determined according to the grating depth and the laser wavelength;

[0014] The first-order diffraction field of the sub-unit is determined based on the light intensity of the writing line light field and the incident light spot, and the writing line light field is determined based on the first-order diffraction field of the sub-unit.

[0015] In one embodiment, the incident light spot is input into the grating light valve, and it is determined whether a subunit of the grating light valve is in a diffraction state, including:

[0016] Determine whether the movable bar in the grating light valve has been displaced;

[0017] If so, then the sub-unit of the grating light valve corresponding to the movable bar is determined to be in a diffraction state.

[0018] In one embodiment, grayscale texturing of the microlens is performed based on the rotating light field, the texturing line light field, and the target light intensity distribution gradient, including:

[0019] The writing area is determined based on the rotating light field, and the regional illumination intensity corresponding to the writing area is determined based on the writing line light field.

[0020] Adjust the working state of the subunit of the grating light valve according to the light field size of the written line light field;

[0021] The illumination intensity of the region is adjusted based on the target light intensity distribution gradient, and the microlens is grayscale-etched according to the adjusted regional illumination intensity through the subunit of the adjusted grating light valve.

[0022] In one embodiment, the illumination intensity of the region is adjusted based on the target light intensity distribution gradient, and the microlens is grayscale-etched according to the adjusted regional illumination intensity through a subunit of the adjusted grating light valve, including:

[0023] During the grayscale writing process, it is determined in real time whether the sub-region being written is a lighting adjustment area;

[0024] If so, the illumination intensity of the region corresponding to the illumination adjustment area is adjusted based on the target light intensity distribution gradient to determine the updated illumination intensity;

[0025] The microlens is grayscale-etched based on the regional illumination intensity and the updated illumination intensity through the adjusted grating light valve subunit.

[0026] In one embodiment, determining the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens includes:

[0027] The curvature information of the microlens is determined based on the surface structure of the microlens;

[0028] The target light intensity distribution gradient of the inscribed line light field is determined based on the curvature information.

[0029] In one embodiment, determining the incident light spot of the grating light valve based on the laser beam emitted from the laser source includes:

[0030] Based on the optical window of the grating light valve, the laser beam emitted from the laser source is laser shaped by a one-dimensional beam expander system to determine the incident light spot of the grating light valve.

[0031] Secondly, this application also provides a grayscale writing apparatus for a microlens, the apparatus comprising:

[0032] The incident spot determination module is used to determine the incident spot of the grating light valve based on the laser beam emitted from the laser source.

[0033] The first-order diffraction field determination module is used to perform phase modulation on the incident light spot through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit.

[0034] The writing line optical field determination module determines the writing line optical field based on the first-order diffraction optical field of the sub-unit;

[0035] The rotating light field determination module is used to rotate the writing line light field through the Daowei prism to determine the rotating light field;

[0036] The light intensity distribution gradient determination module is used to determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens.

[0037] The grayscale writing module is used to perform grayscale writing on the microlens according to the rotating light field, the writing line light field, and the target light intensity distribution gradient.

[0038] Thirdly, this application also provides a computer device, the computer device including a memory and a processor, the memory storing a computer program, and the processor executing the computer program to perform the following steps:

[0039] The incident light spot of the grating light valve is determined based on the laser beam emitted from the laser source;

[0040] The incident light spot is phase-modulated by the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit;

[0041] The writing line light field is determined based on the first-order diffraction light field of the subunit; the writing line light field is rotated by the Dowell prism to determine the rotating light field;

[0042] Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the inscribed line light field is determined;

[0043] The microlens is grayscale etched according to the rotating light field, the etched line light field, and the target light intensity distribution gradient.

[0044] Fourthly, this application also provides a computer-readable storage medium having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0045] The incident light spot of the grating light valve is determined based on the laser beam emitted from the laser source;

[0046] The incident light spot is phase-modulated by the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit;

[0047] The writing line light field is determined based on the first-order diffraction light field of the sub-unit;

[0048] The rotating light field is determined by rotating the writing line light field through a Dove prism.

[0049] Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the inscribed line light field is determined;

[0050] The microlens is grayscale etched according to the rotating light field, the etched line light field, and the target light intensity distribution gradient.

[0051] The aforementioned grayscale writing method, apparatus, computer equipment, and storage medium, when performing grayscale writing on a microlens, modulate the phase of the writing laser through a sub-unit of a grating light valve to determine the first-order diffraction field of the sub-unit. Based on the first-order diffraction field, the writing line light field is determined. A Dowell prism rotates the writing line light field to determine the rotating light field. Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the writing line light field is determined. Grayscale writing is then performed on the microlens based on the rotating light field, the writing line light field, and the target light intensity distribution gradient. This solves the problems of obvious splicing marks on the microlens surface and low processing efficiency during microlens fabrication. By performing grayscale writing on the microlens based on the rotating light field, the writing line light field, and the target light intensity distribution gradient corresponding to the curved surface of the microlens, splicing marks on the microlens surface can be avoided, improving the surface smoothness of the microlens and simultaneously increasing the grayscale writing efficiency. Attached Figure Description

[0052] Figure 1 This is an application environment diagram of a grayscale characterization method in one embodiment;

[0053] Figure 2 This is a flowchart illustrating a grayscale characterization method in one embodiment;

[0054] Figure 3 This is a flowchart illustrating the grayscale writing method in another embodiment;

[0055] Figure 4 This is a flowchart illustrating the grayscale writing method in another embodiment;

[0056] Figure 5 This is a flowchart illustrating the grayscale writing method in another embodiment;

[0057] Figure 6 This is a structural example diagram of a microlens grayscale writing system in another embodiment;

[0058] Figure 7 This is an example diagram of the rotation of the Dowell prism in one embodiment;

[0059] Figure 8 This is a structural example diagram of a grating light valve in one embodiment;

[0060] Figure 9 This is a schematic diagram illustrating the relationship between inscription height and light intensity in one embodiment;

[0061] Figure 10 This is an example diagram illustrating the rotational scanning of the line light field in one embodiment;

[0062] Figure 11 This is a structural block diagram of a microlens grayscale writing device in one embodiment;

[0063] Figure 12 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0065] The grayscale writing method provided in this application embodiment can be applied to, for example... Figure 1In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be integrated onto server 104 or placed on a cloud or other network server. Server 104 determines the incident light spot of the grating valve based on the laser beam emitted from the laser source; it performs phase modulation on the incident light spot through the sub-units of the grating valve to determine the first-order diffraction field of the sub-unit; it determines the writing line light field based on the first-order diffraction field of the sub-unit; it rotates the writing line light field through a Dove prism to determine the rotating light field; it determines the target light intensity distribution gradient of the writing line light field based on the curved surface structure of the microlens; it performs grayscale writing on the microlens based on the rotating light field, the writing line light field, and the target light intensity distribution gradient, and sends the writing progress to terminal 102 via the communication network. Terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can include smart speakers, smart TVs, smart air conditioners, smart vehicle devices, etc. Portable wearable devices can include smartwatches, smart bracelets, and head-mounted devices. Server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0066] In one embodiment, such as Figure 2 As shown, a grayscale writing method is provided. This embodiment illustrates the application of this method to a terminal. It is understood that this method can also be applied to a server, and further to a system including both a terminal and a server, and implemented through interaction between the terminal and the server. In this embodiment, the method includes the following steps:

[0067] S210. Determine the incident light spot of the grating light valve based on the laser beam emitted from the laser source.

[0068] The grating light valve is a light modulation device composed of thousands of sub-units. Each sub-unit consists of multiple fixed and movable strips. The intensity of the first-order diffracted light in the sub-unit is changed by moving the movable strips up and down. When the movable and fixed strips are on the same plane, the light can be reflected back along its original path, and the first-order diffracted light is in a dark state. When electrostatic force is applied, moving the spaced-apart movable strips downwards, the sub-unit enters a diffraction state. At this time, the intensity of the reflected light decreases successively while the intensity of the first-order diffracted light increases. The laser source is also known as the laser writing device, and the laser beam is the laser writing laser.

[0069] Specifically, when grayscale writing is required for a microlens, the microlens's contour parameters are preset. These parameters can include the microlens's aperture and curvature. The operating state of the peripheral subunits of the grating valve is adjusted according to the microlens's aperture. For example, based on the microlens's contour parameters, the outermost subunits of the grating valve can be symmetrically closed around the center of the optical window of the grating valve, so that the first-order diffraction light of the sub-spot output by the closed subunits is in a dark state. This controls the size of the writing line light field. Using this writing line light field for rotational scanning, grayscale writing can be performed on microlenses of any aperture. Generally, when performing grayscale writing on larger aperture microlenses, the peripheral subunits of the grating valve are not closed or are only partially closed; when performing grayscale writing on smaller aperture microlenses, more peripheral subunits of the grating valve are closed. The incident light spot at the optical window of the grating valve is determined based on the laser beam emitted from the laser source.

[0070] S220. The incident light spot is phase-modulated by the sub-unit of the grating valve to determine the first-order diffraction field of the sub-unit.

[0071] It should be noted that the optical window of the grating light valve is a long, linear shape. The grating light valve is composed of thousands of sub-units arranged horizontally in a linear array. Each sub-unit can output a first-order diffraction light field. The first-order diffraction light field of a sub-unit of the grating light valve corresponds to a sub-spot. That is, each sub-region of the writing line light field is composed of each sub-spot.

[0072] Specifically, based on the contour parameters of the microlens, the intensity of the sub-spot to be output by each sub-unit is determined. According to the determined intensity of the sub-spot, the incident spot is phase-modulated by each sub-unit of the grating valve to determine the first-order diffraction light output by each sub-unit.

[0073] S230. Determine the writing line light field based on the first-order diffraction light field of the subunit.

[0074] It should be noted that by independently controlling the intensity and switching of the sub-spots output by each sub-unit, a writing line light field with arbitrary intensity distribution and arbitrary size can be obtained.

[0075] Specifically, the writing line light field is formed by the first-order diffraction light output from each subunit of the grating light valve.

[0076] S240. The writing line light field is rotated by the Dowell prism to determine the rotating light field.

[0077] Among them, the Dove prism is an image rotator. Because the writing line light field has a strip-shaped light field structure, it is necessary to rotate the writing line light field to determine the overall structure of the microlens.

[0078] Specifically, the Dowell prism can be mounted on a high-speed rotator. The mechanical components are controlled by electrical means to rotate, causing the Dowell prism to rotate at high speed. The writing line light field is then directed into the Dowell prism, and the high-speed rotation of the prism causes the writing line light field to rotate axially along its central axis. A 180° rotation completes the scanning and writing of a microlens. The axial rotation angle of the writing line light field is twice the rotation angle of the Dowell prism.

[0079] S250. Based on the curved surface structure of the microlens, determine the target light intensity distribution gradient of the inscribed line light field.

[0080] Specifically, the rotating light field can be divided into several sub-regions, each corresponding to a sub-region of a microlens. The higher the sub-region on the microlens's surface, the higher its corresponding light field intensity; conversely, the lower the sub-region, the lower its corresponding light field intensity. For example, the light field intensity is highest in the sub-region corresponding to the center of the microlens and lowest in the sub-region corresponding to the outermost edge. The height variation information of each region of the microlens can be determined based on its surface structure, and the target intensity distribution gradient of the inscribed line light field can be determined based on this height variation information.

[0081] S260. Grayscale characterization is performed on the microlens based on the rotating light field, the characterization line light field, and the target light intensity distribution gradient.

[0082] Specifically, an imaging system consisting of a sleeve lens and an objective lens images the light field on the surface of the grating light valve onto a displacement stage on which the photolithography sample is placed. The writing profile of the microlens is determined based on the rotating light field. The illumination intensity corresponding to each region in the writing profile of the microlens is determined based on the writing line light field. The illumination intensity is adjusted according to the target light intensity distribution gradient. The writing area of ​​the photolithography sample is determined based on the writing profile of the microlens. Photolithography is performed on the focal plane of the objective lens in the writing area according to the adjusted illumination intensity to achieve grayscale writing of the microlens.

[0083] In the aforementioned grayscale characterization method for microlenses, during grayscale characterization, the characterization laser is phase-modulated through a sub-unit of a grating light valve to determine the first-order diffraction field of the sub-unit. The characterization line light field is then determined based on this first-order diffraction field. A Dove prism rotates the characterization line light field to determine the rotating light field. Based on the curved surface structure of the microlens, the target intensity distribution gradient of the characterization line light field is determined. Grayscale characterization of the microlens is then performed based on the rotating light field, the characterization line light field, and the target intensity distribution gradient. This method solves the problems of obvious splicing marks on the microlens surface and low processing efficiency during microlens fabrication. By characterizing the microlens based on the rotating light field, the characterization line light field, and the target intensity distribution gradient corresponding to the curved surface of the microlens, splicing marks on the microlens surface can be avoided, improving the surface smoothness and simultaneously increasing the grayscale characterization efficiency.

[0084] Preferably, based on the above embodiments, the method for determining the incident spot of the grating light valve according to the laser beam emitted by the laser source can be: based on the optical window of the grating light valve, the laser beam emitted by the laser source is laser shaped by a one-dimensional beam expander system to determine the incident spot of the grating light valve.

[0085] The one-dimensional beam expander system can be a 4F system composed of two cylindrical lenses, or any other optical element that can shape the light spot into a linear light spot covering the optical window of the grating valve.

[0086] Specifically, the optical window of the grating light valve is a long, linear shape, which allows the laser to completely cover the optical window of the grating light valve. Before the laser beam enters the optical window of the grating light valve, a one-dimensional beam expander is introduced to shape the laser beam into a linear optical field that matches the window of the grating light valve, and the linear optical field after the laser beam is shaped is used as the incident light spot of the grating light valve.

[0087] The above scheme can shape the laser beam to determine the incident spot before the laser beam is injected into the optical window of the grating valve, which can improve the matching degree between the incident spot and the optical window.

[0088] In one embodiment, such as Figure 3 As shown, the incident light spot is phase-modulated by a sub-unit of the grating optical valve to determine the first-order diffraction field of the sub-unit, including:

[0089] S310. Input the incident light spot into the grating light valve and determine whether the sub-unit of the grating light valve is in a diffraction state.

[0090] Specifically, the incident light spot is directed into the grating valve through its optical window, while simultaneously determining whether each sub-unit of the grating valve is in a diffraction state.

[0091] For example, a method to determine whether a subunit of a grating light valve is in a diffraction state may be: determining whether the movable strip in the grating light valve has a displacement; if so, determining that the subunit of the grating light valve corresponding to the movable strip is in a diffraction state.

[0092] Specifically, the grating light valve subunit generally contains several strip structures, which are divided into fixed strips and movable strips. The fixed strips and movable strips are arranged alternately. The fixed strips are stationary, while the movable strips can be driven by voltage to move downwards. When the movable strips are not driven by voltage, they will not move and will remain in the same position as the fixed strips. The subunit can act as a plane mirror to reflect the incident light spot back along the original path. At this time, the subunit is in the dark state of first-order diffraction light. Since the first-order diffraction light is used as the writing line light field to write the grayscale of the microlens, when the subunit is in the dark state of first-order diffraction light, it is equivalent to the corresponding sub-spot on the writing line light field being closed. Applying voltage to the movable strips can make them move downwards. At this time, a phase grating can be formed on the surface of the subunit, making the subunit diffracted. At this time, the subunit is in the bright state of first-order diffraction light, and the formula for calculating the diffraction angle is shown in formula (1).

[0093] (1)

[0094] in, The distance between movable bars. λ is the laser wavelength of the laser beam, and m is the diffraction order. It is the diffraction angle.

[0095] Determining whether a sub-unit of a grating optical valve is in a diffraction state by observing whether the movable strip in the grating optical valve is displaced can improve the efficiency of judging whether a sub-unit is in a diffraction state.

[0096] S320. If so, the grating depth is determined according to the laser wavelength of the laser beam, and the intensity of the first-order diffracted light of the sub-unit is determined according to the grating depth and the laser wavelength.

[0097] Specifically, if the sub-unit of the grating light valve is in a diffraction state, the grating depth is determined based on the laser wavelength of the laser beam. When a voltage is applied to the movable bar of the sub-unit, making the grating depth one-quarter of the laser wavelength, the sub-unit is in a diffraction state, and the first-order diffracted light emitted by the sub-unit is the strongest. The driving voltage is controlled to keep the grating depth between 0 and... The intensity of the first-order diffracted light emitted from each subunit can be precisely and continuously varied, allowing control over the intensity of the light emitted from each subunit. The formula for calculating the intensity of the first-order diffracted light is shown in formula (2):

[0098] (2)

[0099] in, The intensity of the first-order diffracted light. This is the maximum light intensity that first-order diffraction light can achieve. denoted as grating depth.

[0100] S330. Determine the first-order diffraction field of the subunit based on the light intensity of the writing line light field and the incident light spot, and determine the writing line light field based on the first-order diffraction field of the subunit.

[0101] Specifically, the incident light spot is diffracted by each sub-unit of the grating light valve so that the first-order diffracted light of each sub-unit meets the light intensity requirements of the writing line light field, and the first-order diffracted light of each sub-unit can form the writing line light field.

[0102] The above scheme uses phase modulation of the corresponding incident light spot by each sub-unit of the grating optical valve to determine the first-order diffraction light output by each sub-unit, and determines the writing line light field based on the first-order diffraction light output by each sub-unit. Parallel processing of the incident light spot by the sub-units of the grating optical valve improves the efficiency of determining the first-order diffraction light field. Furthermore, since the illumination intensity corresponding to the sub-spots forming the writing line light field is adjustable, it can satisfy the continuous grayscale writing of microlenses with arbitrary curved surfaces, improving the flexibility of grayscale writing, reducing microlens splicing marks, and improving the surface quality of the microlenses.

[0103] In one embodiment, such as Figure 4 As shown, grayscale characterization of the microlens is performed based on the rotating light field, the characterization line light field, and the target light intensity distribution gradient, including:

[0104] S410. Determine the writing area based on the rotating light field, and determine the regional illumination intensity corresponding to the writing area based on the light field of the writing line.

[0105] Among them, regional illumination intensity refers to the illumination intensity corresponding to each sub-region in the inscribed region.

[0106] Specifically, the writing area on the photolithographic sample is determined based on the rotating light field, the illumination intensity of the rotating light field is determined based on the illumination intensity of the writing line light field, and the regional illumination intensity corresponding to each sub-region in the writing area is determined based on the illumination intensity of the rotating light field.

[0107] S420. Adjust the working state of the sub-unit of the grating valve according to the light field size of the writing line light field.

[0108] Specifically, based on the size of the writing line light field, the outermost sub-units of the closed grating valve are adjusted with the center of the optical window as the axis, so that the sub-spots corresponding to the closed sub-units are in a dark state, and the size of the linear light field formed by the sub-spots emitted from the adjusted sub-units of the grating valve is consistent with the size of the writing line light field. By rotating and scanning the writing line light field using a Dove prism, microlens structures of arbitrary apertures can be written.

[0109] S430. Adjust the illumination intensity of the region based on the target light intensity distribution gradient, and perform grayscale characterization on the microlens according to the adjusted regional illumination intensity through the subunit of the adjusted grating light valve.

[0110] For example, the method of adjusting the regional illumination intensity based on the target light intensity distribution gradient and performing grayscale characterization on the microlens according to the adjusted regional illumination intensity can be as follows: during the grayscale characterization process, it is determined in real time whether the characterized sub-region is an illumination adjustment region; if so, the regional illumination intensity corresponding to the illumination adjustment region is adjusted based on the target light intensity distribution gradient to determine the updated illumination intensity; and the microlens is then subjected to grayscale characterization according to the regional illumination intensity and the updated illumination intensity through the sub-unit of the adjusted grating light valve.

[0111] Theoretically, the writing end position and the writing start position should be the same. However, during grayscale writing, the start and end positions of the writing line light field scanning lithography sample may cause splicing marks to appear on the fabricated microlenses. The sub-region being written is the area that will be written during the grayscale writing process.

[0112] Specifically, during the grayscale inscription process, it is determined in real time whether the inscribed sub-region is an illumination adjustment region. If the inscribed sub-region is a splicing region, it is determined to be an illumination adjustment region. If the inscribed sub-region is an illumination adjustment region, the illumination intensity of the corresponding region is adjusted based on the target light intensity distribution gradient to determine the updated illumination intensity. Through the sub-unit of the adjusted grating valve, the other regions in the inscription area, excluding the illumination adjustment region, are inscribed according to the regional illumination intensity, and the illumination adjustment region is inscribed according to the updated illumination intensity.

[0113] For example, the starting position of the lithographic sample scanned by the writing line light field can be used as the writing end position, and the illumination adjustment area can be determined from the writing area based on the writing end position. For example, the writing area near the writing end position can be used as the illumination adjustment area.

[0114] The above scheme, since the probability of splicing marks appearing at the start and end positions of the writing line light field scanning is relatively high, determines the illumination adjustment area from the writing area based on the writing end position, and adjusts the illumination intensity of the area corresponding to the illumination adjustment area to fine-tune the intensity distribution of the writing line light field at the writing end position. This can reduce the splicing marks on the surface of the processed microlens, further optimize the surface quality of the microlens, and improve the grayscale writing efficiency of the microlens.

[0115] Adjusting the regional illumination intensity based on the target light intensity distribution gradient and then performing grayscale characterization on the microlens according to the adjusted regional illumination intensity can improve the smoothness of the fabricated microlens surface.

[0116] In one embodiment, such as Figure 5 As shown, based on the curved surface structure of the microlens, the target light intensity distribution gradient of the characterizing line light field is determined, including:

[0117] S510. Determine the curvature information of the microlens based on the surface structure of the microlens.

[0118] Specifically, the contour parameters of the microlens are determined based on the curved surface structure of the microlens, and the curvature information of the microlens is calculated based on the contour parameters.

[0119] S520. Determine the target light intensity distribution gradient of the inscribed line light field based on the curvature information.

[0120] Specifically, microlenses with higher curvature correspond to a larger light intensity distribution gradient, while microlenses with lower curvature correspond to a smaller light intensity. Therefore, the light intensity distribution gradient of the inscribed line light field is designed based on the radius of curvature of the processed lens. Inscribing microlenses with high radii of curvature can increase the light intensity gradient from the center to both ends of the inscribed line light field, while inscribing microlenses with low radii of curvature can decrease the light intensity gradient from the center to both ends of the inscribed line light field. For example, the correspondence between curvature values ​​and light intensity gradients can be preset, and based on the curvature information and the correspondence between curvature values ​​and light intensity gradients, the light intensity gradient corresponding to the curvature information of the microlens can be determined as the target light intensity distribution gradient for inscribing the line light field.

[0121] The above scheme determines the target light intensity distribution gradient of the inscribed line light field based on the curvature information of the microlens, which can improve the efficiency of determining the target light intensity distribution gradient while ensuring the accuracy of the target light intensity gradient.

[0122] For example, based on the above embodiments, the grayscale characterization method for microlenses can be applied to a grayscale characterization system for microlenses, such as... Figure 6 As shown, the grayscale writing system of the microlens includes: a laser source 1, a one-dimensional beam expander 2, a grating light valve 3, a Dowell prism 4, a sleeve lens 5, an objective lens 6, and a displacement stage 7 on which the photolithographic sample is placed.

[0123] The laser beam emitted by the laser source is generally a small-diameter circular outline spot with a Gaussian intensity distribution. By using a one-dimensional beam expander system to shape the laser beam emitted by the laser source, a linear spot that can completely cover the window of the grating valve can be formed. The linear spot is then used as the incident spot of the grating valve and is incident perpendicularly onto the surface of the grating valve.

[0124] The grating light valve possesses the properties of a diffraction grating, and its first-order diffracted light is used as the writing line light field for grayscale writing of the microlens. The writing line light field emitted from the grating light valve is incident on a Dowell prism mounted on a high-speed rotator, and the Dowell prism... Figure 7 As shown, the Dove prism acts as an image rotator, rotating the incident writing line light field. When the rotation angle of the Dove prism is θ, the rotation angle of the writing line light field is 2θ. The writing line light field emitted from the Dove prism is then incident on the imaging system composed of the sleeve lens and the objective lens. Based on the writing line light field emitted from the Dove prism, the light field on the surface of the grating light valve is imaged onto the focal plane of the objective lens within the photolithographic sample for writing.

[0125] The internal structure of the grating light valve is as follows Figure 8 As shown, the grating optical valve has several sub-units arranged horizontally, and each sub-unit contains several strip structures. These strip structures are arranged periodically and parallel vertically. The strip structures within the sub-unit are divided into fixed strips and movable strips, which are arranged alternately. The fixed strips remain stationary, while the movable strips can be displaced downwards under voltage. When there is no voltage driving, the movable strips do not move and remain in the same position as the fixed strips. The sub-unit acts as a plane mirror, reflecting the incident light spot back along its original path. At this time, the sub-unit is in the dark state of first-order diffraction. Since first-order diffraction is used as the writing line light field to write the grayscale of the microlens, when the sub-unit is in the dark state of first-order diffraction, it is equivalent to the corresponding sub-spot being closed on the writing line light field. Applying voltage to the movable strips causes them to move downwards. At this time, a phase grating can be formed on the surface of the sub-unit, putting the sub-unit in a diffraction state. The sub-unit is now in the bright state of first-order diffraction, equivalent to the corresponding sub-spot being opened on the writing line light field. A grating light valve can phase-modulate an incident linear light spot to output a writing line light field with arbitrary intensity distribution. Each sub-spot in the writing line light field corresponds to a first-order diffracted beam output from a sub-unit of the grating light valve. Each sub-unit can independently control its sub-spot to be in a dark or bright state. By independently controlling the intensity and on / off state of the sub-spots through each sub-unit of the grating light valve, writing line light fields with arbitrary intensity distribution and size can be obtained. The downward movement distance of the movable strip within the sub-unit can be 0~ The intensity of the writing light is continuously varied between 4 and 6, thereby controlling the illumination intensity of each sub-spot. Since the writing light has different illumination intensities, the writing height also changes with the illumination intensity, thus achieving grayscale writing of the microlens. The relationship between writing height and illumination intensity is as follows: Figure 9 As shown.

[0126] The writing line optical field is rotated and scanned along its central axis by rotating the Dove prism. An example of the rotating scanning of the writing line optical field is shown in the figure below. Figure 10As shown, a microlens can be scanned and written by rotating the writing line light field by 180°. During microlens writing, the size and intensity distribution of the writing line light field are first adjusted according to the target parameters of the microlens. The illumination intensity of the sub-spot corresponding to the central region of the microlens is the highest, while the illumination intensity of the sub-spot corresponding to the outermost region of the microlens is the lowest. Based on the size of the writing line light field, the outermost sub-units of the grating valve are adjusted and closed, with the center of the optical window of the grating valve as the axis, so that the sub-spots corresponding to the closed sub-units are in a dark state. By rotating and scanning the writing line light field using a Dove prism, microlens structures of arbitrary apertures can be written. Furthermore, the intensity distribution gradient of the writing line light field is adjusted according to the radius of curvature of the microlens. The larger the radius of curvature of the microlens, the larger the grayscale gradient of the curved surface structure, requiring a larger intensity distribution gradient of the writing line light field. Meanwhile, during the microlens writing process, considering that splicing marks may appear at the start and end of the scan, the intensity distribution of the writing line light field at the splicing position can be continuously fine-tuned and optimized to reduce or even eliminate splicing marks, thereby further optimizing the surface quality of the microlens.

[0127] In the aforementioned grayscale characterization method for microlenses, during grayscale characterization, the characterization laser is phase-modulated through a sub-unit of a grating light valve to determine the first-order diffraction field of the sub-unit. The characterization line light field is then determined based on this first-order diffraction field. A Dove prism rotates the characterization line light field to determine the rotating light field. Based on the curved surface structure of the microlens, the target intensity distribution gradient of the characterization line light field is determined. Grayscale characterization of the microlens is then performed based on the rotating light field, the characterization line light field, and the target intensity distribution gradient. This method solves the problems of obvious splicing marks on the microlens surface and low processing efficiency during microlens fabrication. By characterizing the microlens based on the rotating light field, the characterization line light field, and the target intensity distribution gradient corresponding to the curved surface of the microlens, splicing marks on the microlens surface can be avoided, improving the surface smoothness and simultaneously increasing the grayscale characterization efficiency.

[0128] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0129] Based on the same inventive concept, this application also provides a grayscale writing apparatus for implementing the grayscale writing method described above. The solution provided by this apparatus is similar to the solution described in the above method. Therefore, the specific limitations of one or more grayscale writing apparatus embodiments provided below can be found in the limitations of the grayscale writing method for microlenses above, and will not be repeated here.

[0130] In one embodiment, such as Figure 11 As shown, a grayscale marking device for a microlens is provided, comprising: an incident light spot determination module 601, a first-order diffraction light field determination module 602, a marking line light field determination module 603, a rotating light field determination module 604, a light intensity distribution gradient determination module 605, and a grayscale marking module 606, wherein:

[0131] Incident spot determination module 601 is used to determine the incident spot of the grating light valve based on the laser beam emitted from the laser source;

[0132] The first-order diffraction field determination module 602 is used to perform phase modulation on the incident light spot through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit.

[0133] The writing line optical field determination module 603 is used to determine the writing line optical field based on the first-order diffraction optical field of the sub-unit;

[0134] The rotating light field determination module 604 is used to determine the rotating light field by rotating the writing line light field through the Daowei prism.

[0135] The light intensity distribution gradient determination module 605 is used to determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens.

[0136] The grayscale writing module 606 is used to perform grayscale writing on the microlens based on the rotating light field, the writing line light field, and the target light intensity distribution gradient.

[0137] The aforementioned grayscale writing device for microlenses modulates the writing laser phase through a sub-unit of a grating valve during grayscale writing, determining the first-order diffraction field of the sub-unit. Based on this first-order diffraction field, the writing line field is determined. A Dowell prism rotates the writing line field, determining the rotating field. The target intensity distribution gradient of the writing line field is determined based on the curved surface structure of the microlens. Grayscale writing is then performed on the microlens based on the rotating field, the writing line field, and the target intensity distribution gradient. This solves the problems of obvious splicing marks and low processing efficiency in microlens fabrication. By using the rotating field, the writing line field, and the target intensity distribution gradient corresponding to the curved surface of the microlens for grayscale writing, splicing marks on the microlens surface can be avoided, improving the surface smoothness and simultaneously increasing the grayscale writing efficiency.

[0138] For example, the first-order diffraction field determination module 602 is specifically used for:

[0139] The incident light spot is input into the grating light valve, and it is determined whether the sub-unit of the grating light valve is in a diffraction state.

[0140] If so, the grating depth is determined based on the laser wavelength of the laser beam, and the intensity of the first-order diffracted light of the sub-unit is determined based on the grating depth and the laser wavelength.

[0141] The first-order diffraction field of the subunit is determined based on the intensity of the writing line light field and the incident light spot, and the writing line light field is determined based on the first-order diffraction field of the subunit.

[0142] Furthermore, the first-order diffraction field determination module 602 is also specifically used for:

[0143] Determine whether the movable bar in the grating light valve has been displaced;

[0144] If so, then the sub-unit of the grating light valve corresponding to the movable bar is determined to be in a diffraction state.

[0145] For example, the grayscale writing module 606 is specifically used for:

[0146] The writing area is determined based on the rotating light field, and the regional illumination intensity corresponding to the writing area is determined based on the writing line light field.

[0147] Adjust the working state of the sub-unit of the grating light valve according to the light field size of the writing line light field;

[0148] The regional illumination intensity is adjusted based on the target light intensity distribution gradient, and the microlens is grayscale-etched according to the adjusted regional illumination intensity through the sub-unit of the grating light valve.

[0149] Furthermore, the grayscale writing module 606 is also specifically used for:

[0150] During the grayscale writing process, it is determined in real time whether the sub-region being written is a lighting adjustment area;

[0151] If so, the illumination intensity of the corresponding area in the illumination adjustment area is adjusted based on the target light intensity distribution gradient to determine the updated illumination intensity;

[0152] The microlens is grayscale-etched based on the regional illumination intensity and the updated illumination intensity by using the adjusted sub-unit of the grating light valve.

[0153] For example, the light intensity distribution gradient determination module 605 is specifically used for:

[0154] The curvature information of the microlens is determined based on the surface structure of the microlens;

[0155] The target light intensity distribution gradient of the inscribed line light field is determined based on the curvature information.

[0156] For example, the incident light spot determination module 601 is specifically used for:

[0157] Based on the optical window of the grating light valve, the laser beam emitted from the laser source is laser shaped by a one-dimensional beam expander system to determine the incident light spot of the grating light valve.

[0158] Each module in the aforementioned grayscale writing device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0159] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 12As shown, the computer device includes a processor, memory, input / output interfaces, a communication interface, a display unit, and an input device. The processor, memory, and input / output interfaces are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interfaces. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The input / output interfaces are used for exchanging information between the processor and external devices. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a grayscale writing method. The display unit is used to form a visually visible image and can be a display screen, a projection device, or a virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0160] Those skilled in the art will understand that Figure 12 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0161] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0162] Step 1: Determine the incident light spot of the grating light valve based on the laser beam emitted from the laser source;

[0163] Step 2: Phase modulation of the incident light spot is performed through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit;

[0164] Step 3: Determine the writing line light field based on the first-order diffraction light field of the sub-unit;

[0165] Step 4: Rotate the writing line light field using the Dowell prism to determine the rotating light field;

[0166] Step 5: Determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens;

[0167] Step 6: Perform grayscale characterization on the microlens based on the rotating light field, the characterization line light field, and the target light intensity distribution gradient.

[0168] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program performing the following steps when executed by a processor:

[0169] Step 1: Determine the incident light spot of the grating light valve based on the laser beam emitted from the laser source;

[0170] Step 2: Phase modulation of the incident light spot is performed through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit;

[0171] Step 3: Determine the writing line light field based on the first-order diffraction light field of the sub-unit;

[0172] Step 4: Rotate the writing line light field using the Dowell prism to determine the rotating light field;

[0173] Step 5: Determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens;

[0174] Step 6: Perform grayscale characterization on the microlens based on the rotating light field, the characterization line light field, and the target light intensity distribution gradient.

[0175] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, performs the following steps:

[0176] Step 1: Determine the incident light spot of the grating light valve based on the laser beam emitted from the laser source;

[0177] Step 2: Phase modulation of the incident light spot is performed through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit;

[0178] Step 3: Determine the writing line light field based on the first-order diffraction light field of the sub-unit;

[0179] Step 4: Rotate the writing line light field using the Dowell prism to determine the rotating light field;

[0180] Step 5: Determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens;

[0181] Step 6: Perform grayscale characterization on the microlens based on the rotating light field, the characterization line light field, and the target light intensity distribution gradient.

[0182] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions.

[0183] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0184] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0185] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for grayscale characterization of a microlens, characterized in that, include: The incident light spot of the grating light valve is determined based on the laser beam emitted from the laser source; The incident light spot is phase-modulated by the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit; The writing line light field is determined based on the first-order diffraction light field of the sub-unit; The rotating light field is determined by rotating the writing line light field through a Dove prism. Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the inscribed line light field is determined; The microlens is grayscale etched according to the rotating light field, the etched line light field, and the target light intensity distribution gradient.

2. The method according to claim 1, characterized in that, Phase modulation of the incident light spot by the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit includes: The incident light spot is input into the grating light valve, and it is determined whether the sub-unit of the grating light valve is in a diffraction state; If so, the grating depth is determined according to the laser wavelength of the laser beam, and the light intensity of the first-order diffracted light of the sub-unit is determined according to the grating depth and the laser wavelength; The first-order diffraction field of the sub-unit is determined based on the light intensity of the writing line light field and the incident light spot, and the writing line light field is determined based on the first-order diffraction field of the sub-unit.

3. The method according to claim 2, characterized in that, Inputting the incident light spot into the grating light valve and determining whether a subunit of the grating light valve is in a diffraction state includes: Determine whether the movable bar in the grating light valve has been displaced; If so, then the sub-unit of the grating light valve corresponding to the movable bar is determined to be in a diffraction state.

4. The method according to claim 1, characterized in that, The microlens is grayscale-etched according to the rotating light field, the etched line light field, and the target light intensity distribution gradient, including: The writing area is determined based on the rotating light field, and the regional illumination intensity corresponding to the writing area is determined based on the writing line light field. Adjust the working state of the subunit of the grating light valve according to the light field size of the written line light field; The illumination intensity of the region is adjusted based on the target light intensity distribution gradient, and the microlens is grayscale-etched according to the adjusted regional illumination intensity through the subunit of the adjusted grating light valve.

5. The method according to claim 4, characterized in that, The illumination intensity of the region is adjusted based on the target light intensity distribution gradient, and the microlens is grayscale-etched according to the adjusted regional illumination intensity through the subunit of the adjusted grating light valve, including: During the grayscale writing process, it is determined in real time whether the sub-region being written is a lighting adjustment area; If so, the illumination intensity of the region corresponding to the illumination adjustment area is adjusted based on the target light intensity distribution gradient to determine the updated illumination intensity; The microlens is grayscale-etched based on the regional illumination intensity and the updated illumination intensity through the adjusted grating light valve subunit.

6. The method according to claim 1, characterized in that, Based on the curved surface structure of the microlens, the target light intensity distribution gradient of the inscribed line light field is determined, including: The curvature information of the microlens is determined based on the surface structure of the microlens; The target light intensity distribution gradient of the inscribed line light field is determined based on the curvature information.

7. The method according to claim 1, characterized in that, The incident light spot of the grating light valve is determined based on the laser beam emitted from the laser source, including: Based on the optical window of the grating light valve, the laser beam emitted from the laser source is laser shaped by a one-dimensional beam expander system to determine the incident light spot of the grating light valve.

8. A grayscale writing device for a microlens, characterized in that, The grayscale writing device for the microlens includes: The incident spot determination module is used to determine the incident spot of the grating light valve based on the laser beam emitted from the laser source. The first-order diffraction field determination module is used to perform phase modulation on the incident light spot through the sub-unit of the grating light valve to determine the first-order diffraction field of the sub-unit. The writing line optical field determination module is used to determine the writing line optical field based on the first-order diffraction optical field of the sub-unit; The rotating light field determination module is used to rotate the writing line light field through the Daowei prism to determine the rotating light field; The light intensity distribution gradient determination module is used to determine the target light intensity distribution gradient of the inscribed line light field based on the curved surface structure of the microlens. The grayscale writing module is used to perform grayscale writing on the microlens according to the rotating light field, the writing line light field, and the target light intensity distribution gradient.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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