Laser direct writing system and scanning method thereof

Abstract

A laser direct writing system and a scanning method thereof, the laser direct writing system comprising a graphics generator and a control system, the control system comprising a pattern acquisition unit, different pattern parameters are acquired by the pattern acquisition unit, rasterization operation is performed on vector graphics according to different pattern parameters to obtain rasterized image data, and whether to perform data expansion on the rasterized image data is selected according to different pattern parameters. For a pattern that requires rasterized image data expansion, rasterization expansion is performed first and then conversion and storage of the rasterized data is performed. For a pattern that does not require rasterized image data expansion, rasterization data is directly converted and stored, and frame processing is performed based on the converted and stored rasterized data, so as to meet the needs of workpieces with various pattern parameters.

Description

Technical Field

[0001] The invention relates to a scanning method, in particular to a scanning method suitable for the field of laser direct writing. Background Art

[0002] The laser direct writing system, also known as the direct image projection system, can be applied to the research and development and production of semiconductors, PCBs and planar imaging. Its principle is to use a graphic generator to replace the traditional mask technology and directly expose the computer's graphic data to the product, which can save costs and improve efficiency.

[0003] The pattern generator includes a digital micromirror device (DMD), a liquid crystal display, a rotating polygonal mirror scanner or a grating light valve (GLV). A digital micromirror device (DMD) is a micro-electromechanical system with electronic input and optical output, including an array of micro-mirrors with two deflection angles. In practical applications, the light source is projected to the digital micromirror device after being homogenized. The micro-mirrors in the digital micromirror device have two deflection angles α and -α. When the deflection angle of the micro-mirror is α, the micro-mirror projects the light to the subsequent optical system, corresponding to the opening of the digital circuit. When the deflection angle of the micro-mirror is -α, the micro-mirror deflects the light outside the subsequent optical system, corresponding to the closing of the digital circuit. The desired pattern is formed by controlling the deflection angle of the micro-mirror in the digital micromirror device. Usually, α is equal to 12 degrees.

[0004] If the digital micromirror device is used to directly perform projection exposure, since the size of the micromirrors in the digital micromirror device and the spacing between adjacent micromirrors are fixed, the accuracy of the product is fixed and cannot be adjusted as needed. If the digital micromirror device has an inclination angle with the scanning direction of the projection exposure, the spacing between the projection points of adjacent micromirrors perpendicular to the scanning direction varies due to the different inclination angles. By changing the inclination angle, the distance between the projection points becomes smaller, and more pixel processing and more processing data are required to complete an image. This method can increase the accuracy of the product exponentially, but it also means that exponentially more data needs to be processed. The exponential increase in the amount of data leads to a slower data processing speed and a slower exposure speed for the product. And once the inclination angle of the digital micromirror device is determined, the accuracy of the product is determined. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a scanning method for changing the accuracy of a digital micromirror device with a determined inclination angle according to product requirements.

[0006] In order to solve the above problems, the present invention provides a scanning method of a laser direct writing system, wherein the laser direct writing system includes a graphics generator and a control system, and the control system includes a pattern acquisition unit, through which different pattern parameters are acquired, and a rasterization operation is performed on a vector graphic according to different pattern parameters to obtain rasterized image data, and according to different pattern parameters, it is selected whether to perform data expansion on the rasterized image data. For a pattern that requires rasterized image data expansion, rasterization expansion is performed first and then conversion and storage of the rasterized data is performed. For a pattern that does not require rasterized image data expansion, the rasterized data is directly converted and stored, and frame processing is performed based on the converted and stored rasterized data.

[0007] Furthermore, the mode parameter is the subdivision number or resolution of the laser direct writing system.

[0008] Furthermore, the difference between the different mode parameters is 2 n or (1 / 2) n multiple relationship.

[0009] Furthermore, the different mode parameters at least include a subdivision number or a resolution determined according to an inclination angle of the pattern generator relative to a scanning direction.

[0010] Further, for the number of subdivisions or the resolution determined according to the inclination angle of the pattern generator relative to the scanning direction (1 / 2) n The data expansion is performed from one to two times for the subdivided pixel units in the rasterized image. 2n of 2 n Row 2 n The data of the column is expanded, wherein the subdivided pixel unit is the smallest pixel unit in the rasterized image obtained according to the mode parameters.

[0011] Furthermore, when rasterized data is converted and stored, the subdivision number determined by the inclination angle of the graphic generator relative to the scanning direction is used as the data amount of the storage unit for storage, and the data stored in the storage unit constitutes a subdivision pixel block.

[0012] Furthermore, the storage space of the storage unit is greater than the data storage capacity of the subdivision number value determined according to the inclination angle of the pattern generator relative to the scanning direction.

[0013] A laser direct writing system comprises a graphics generator and a control system. The control system comprises a mode acquisition unit, a vector image rasterization unit, a data expansion unit, an image data conversion storage unit and an image data framing processing unit. The mode acquisition unit acquires mode parameters or mode instructions, wherein the mode instructions include mode parameters. The vector image rasterization unit acquires the mode parameters of the mode acquisition unit and performs a rasterization operation on the vector image according to the mode parameters to obtain rasterized image data. If the number of subdivisions indicated by the mode parameters is lower than the number of subdivisions obtained according to the inclination angle of the graphics generator relative to the scanning direction, the rasterized image data is transmitted to the data expansion unit to expand the rasterized image data. The expanded rasterized image data is converted and stored by the image data conversion storage unit. If the number of subdivisions indicated by the mode parameters is equal to the number of subdivisions obtained according to the inclination angle of the graphics generator relative to the scanning direction, the rasterized image data is directly transmitted to the image data conversion storage unit, the rasterized image data is converted and stored by the image data conversion storage unit, and the rasterized image data is processed by the image data framing processing unit to obtain a framed image corresponding to the graphics generator.

[0014] Furthermore, the image data conversion storage unit includes a plurality of subdivision storage units, the storage space of the subdivision storage unit is not less than the storage space of the data amount of the subdivision number value obtained according to the inclination angle of the graphic generator relative to the scanning direction, and each subdivision storage unit stores the data of a subdivision pixel block in a basic pixel unit.

[0015] Furthermore, the pattern generator is a digital micromirror device.

[0016] Compared with the prior art, the laser direct writing system and the scanning method thereof can adapt to the needs of workpieces with various mode parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram of a graphics generator.

[0018] Figure 2 It is a schematic diagram of the pattern generator being deflected by an angle θ relative to the scanning direction.

[0019] Figure 3 This is a schematic diagram of rasterizing some vector images.

[0020] Figure 4 It is a schematic diagram of data expansion of subdivided pixel blocks.

[0021] Figure 5 This is a schematic diagram of a partially rasterized image stretched in the scanning direction.

[0022] Figure 6It is a schematic diagram of the relationship between the deflected graphics generator and the stretched rasterized image.

[0023] Figure 7 It is a schematic diagram of a pixel image of a portion of the graphics generator.

[0024] Figure 8 It is a schematic diagram of stretching a pixel image of a portion of a graphics generator in the sub-scanning direction.

[0025] Fig. 9 It is a schematic block diagram of the control system. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described below by means of specific embodiments shown in the accompanying drawings.

[0027] For the laser direct writing system, it includes a light source component, a pattern generator, an optical component, a carrying system and a control system. The light source component, the pattern generator and the optical component constitute a projection system. The control system controls the synergy between the projection system and the carrying system, including controlling the light source component to emit a light beam; controlling the pattern generator to change the light beam path and finally project it through the optical component to the workpiece placed on the carrying component; controlling the relative movement of the carrying component and the projection system, including the carrying system moving relative to the projection system, or the projection system moving relative to the carrying system. Preferably, the carrying system moves relative to the projection system to ensure the optical accuracy of the projection system, and the carrying system moves relative to the projection system in a scanning direction, or also includes moving in a sub-scanning direction perpendicular to the scanning direction.

[0028] like Figure 1-2As shown, in order to improve the resolution and obtain finer lines, the pattern generator has a deflection angle of θ with the scanning direction. The pattern generator has N rows and M columns of pixel elements 1. In the figure, N=14 and M=18 are taken as an example. When the pattern generator has no inclination with the scanning direction, the row is perpendicular to the scanning direction, the column is parallel to the scanning direction, and the line connecting the pixel images projected by the pixel elements to the workpiece in the scanning direction is the scanning line. The number of pixel elements in the pattern generator that fall on the same scan line determines the K value. In the example, K=2. The value of the angle θ is determined according to the values ​​of N and K. Tan (θ) = K / N. The value of N / K is usually selected as an integer value. N / K represents the minimum interval between pixel units on the same scan line. It also represents the number of parts divided in one direction for the pixel image when no deflection occurs, that is, the number of subdivisions. The figure takes the number of subdivisions as 7 as an example. According to the number of subdivisions, the resolution of the laser direct writing system can be determined. The resolution is the minimum line width that the laser direct writing system can resolve. The resolution of the pattern generator when it is not tilted is N / K times the resolution when it is tilted at an angle θ relative to the scanning direction. For the laser direct writing system, the lower the resolution value, the finer the lines it processes, the higher the resolution level, that is, high resolution; on the contrary, the higher the resolution value, the relatively rougher the lines it processes, the lower the resolution level, that is, low resolution. At the same time, the number of subdivisions increases exponentially, and for the control system, the image data that needs to be processed also increases exponentially.

[0029] After the angle between the pattern generator and the scanning direction is determined, the subdivision number and resolution of the laser direct writing system are determined values. The pattern generator control of the laser direct writing system can only be controlled according to the corresponding subdivision number and resolution. Of course, the laser direct writing system can process workpieces with a resolution higher than the resolution of the laser direct writing system, but because the resolution of the laser direct writing system is low, the resolution level is high, and the subdivision number is high, the image data that needs to be processed increases exponentially. Using a high-resolution laser direct writing system to process workpieces with low resolution requirements will have lower efficiency and production capacity than a low-resolution laser direct writing system. Therefore, the resolution level is usually selected to match the resolution level required by the workpiece.

[0030] In order to enable the laser direct writing system to process workpieces with high resolution requirements that match the resolution requirements, and to quickly process workpieces with low resolution requirements. A processing method for a laser direct writing system is provided, wherein the laser direct writing system includes a pattern generator and a control system, and the laser direct writing system has two working modes: a fine mode with high resolution and a fast mode with low resolution, wherein the number of subdivisions in the fine mode is twice the number of subdivisions in the fast mode, and the number of subdivisions in the fine mode is determined according to the inclination angle of the pattern generator relative to the scanning direction. The laser direct writing system has a mode switching function for switching between the fine mode and the fast mode.

[0031] like Figure 3-8 As shown, in the fast mode, the value of the subdivision number of the fast mode is half of the value of the subdivision number that can be achieved by the laser direct writing system. The vector graphics to be operated are rasterized according to the subdivision number of the fast mode, and the vector graphics are divided into a plurality of basic pixel units 2. The basic pixel unit 2 is Figure 3 In the figure, each basic pixel unit corresponds to a projection pixel unit of a pixel element of a pattern generator that is not tilted. Each basic pixel unit is divided in the scanning direction and the sub-scanning direction according to the subdivision number to obtain a smaller subdivision pixel unit 3. The subdivision pixel unit 3 is Figure 3A row of subdivided pixel units 3 in the basic pixel unit 2 is separated by a thin line frame as a subdivided pixel block 4, and a binary value of 0 or 1 is assigned to each subdivided pixel unit 3 to obtain rasterized image data. The rasterized image data is expanded according to the actual subdivision number determined by the inclination angle of the pattern generator, and each subdivision pixel unit in the subdivision pixel block is expanded in the row direction and the column direction. The data of each subdivision pixel unit in the row direction is copied, and the copied subdivision pixel unit data is assigned the same value as the copied subdivision pixel unit data. If the copied subdivision pixel unit is assigned a value of 1, then the copied subdivision pixel unit and the copied subdivision pixel unit are assigned a value of 11. If the copied subdivision pixel unit is assigned a value of 0, then the copied subdivision pixel unit and the copied subdivision pixel unit are assigned a value of 00. After completing the data expansion of a row of subdivision pixel units, the subdivision pixel unit data is expanded in the column direction, that is, the data of a row of subdivision pixel units is expanded 1 to 1, and the data of a row of subdivision pixel units is copied; or the subdivision pixel unit data is expanded in a row and column direction in a one-to-four manner, and one subdivision pixel unit data is divided into four subdivision pixel unit data with the same assignment, and the four subdivision pixel data are divided into two rows and two columns. The expanded rasterized image data is divided and stored, and a subdivision pixel block is used as a storage unit for storage, and the storage space of the storage unit is not less than the data amount of the subdivision number value of the fine mode. The subdivided pixel blocks are stretched in the scanning direction, and the subdivided pixel blocks in the next column are shifted one row below the previous column of subdivided pixel blocks in the scanning direction. The rasterized image data is stretched in the scanning direction, that is, the row position data of the subdivided pixel blocks are changed accordingly to obtain the stretched rasterized image data. Figure 6-7 As shown ( Figure 7 The part in the dotted line box is not Figure 6 ), according to the row and column relationship of the subdivided pixel blocks in the stretched rasterized image, data is read from the storage units of the subdivided pixel blocks in sequence, and a value is read from each subdivided pixel block. In the column direction, the number of subdivided pixel blocks between adjacent subdivided pixel blocks that read data is the same as the subdivision number value of the fine mode. That is, data is read at intervals of the subdivision number value in both the row direction and the column direction to obtain the pattern generator pixel image. Figure 8As shown, the pixel image of the pattern generator is stretched in the sub-scanning direction, that is, the pixel image of the pattern generator is reversed in the sub-scanning direction, so that the pixel image of the pattern generator returns to a neat square state, and the effective pixel image of the pattern generator is obtained. The framed image of the pattern generator is obtained according to the effective pixel image, and the pixel elements of the pattern generator are controlled according to the framed image. The framed image is a frame image of the workpiece directly projected by the pattern generator. By transforming the framed image at a certain frequency, the exposure of a scanning strip is completed. In the fast mode, in the process of rasterizing the vector graphics, due to the use of a low subdivision number for operation, the amount of data processing can be effectively reduced, and the time of data transmission can also be saved. In the process of converting and storing the rasterized graphics, the data is expanded to meet the data requirements of the pattern generator, and the control of the pattern generator is completed.

[0032] In the fine mode, a rasterization operation is performed on the vector graphics to be operated according to the subdivision number of the fine mode, and the vector graphics is divided into a plurality of basic pixel units, each of which corresponds to a projection pixel unit of a pixel element of a graphic generator that has not been deflected. Each basic pixel unit is divided according to the subdivision number in the scanning direction and the sub-scanning direction to obtain smaller subdivision pixel units, and a row of subdivision pixel units in the basic pixel unit is a subdivision pixel block. A binary value of 0 or 1 is assigned to each subdivision pixel unit to obtain rasterized image data. The rasterized image data is divided and stored, and a subdivision pixel block is used as a storage unit for storage, and the storage space of the subdivision pixel block is not less than the storage space of the data amount of the subdivision number value of the fine mode. The subdivision pixel block is stretched in the scanning direction, and the subdivision pixel block in the latter column is shifted one row below the previous column of subdivision pixel blocks along the scanning direction, so as to realize the stretching of the rasterized image data in the scanning direction, that is, the row position data of the subdivision pixel block is correspondingly changed to obtain the stretched rasterized image data. According to the row-column relationship of the subdivided pixel blocks in the stretched rasterized image, data is read from the storage units of the subdivided pixel blocks in sequence, and a value is read from each subdivided pixel block. In the column direction, the number of subdivided pixel blocks between adjacent subdivided pixel blocks from which data is read is the same as the value of the subdivision number of the fine mode. That is, data is read at intervals of the value of the subdivision number in both the row direction and the column direction to obtain the pixel image of the pattern generator. The pixel image of the pattern generator is stretched in the sub-scanning direction, that is, the pixel pattern of the pattern generator is staggered in the sub-scanning direction so that the pixel image of the pattern generator is restored to a neat square state, and an effective pixel image of the pattern generator is obtained. According to the effective pixel image, a framed image of the pattern generator is obtained. According to the framed image, the pixel elements of the pattern generator are controlled. The framed image is a frame image of the pattern generator directly projecting the workpiece. By transforming the framed image at a certain frequency, the exposure of a scanning strip is completed.

[0033] like Fig. 9As shown, the control system of the laser direct writing system includes a mode acquisition unit, a vector image rasterization unit, a data expansion unit, an image data conversion storage unit, and an image data framing processing unit. The mode acquisition unit acquires mode parameters or mode instructions, and the mode instructions include mode parameters. The vector image rasterization unit acquires the mode parameters of the mode acquisition unit, and performs a rasterization operation on the vector image according to the mode parameters to obtain rasterized image data, that is, the vector image is rasterized according to the requirements for the number of subdivisions in the mode parameters. The mode parameter is the number of subdivisions or resolution, and different mode parameters correspond to different scanning modes. The number of subdivisions or resolution determined according to the inclination angle of the graphic generator relative to the scanning direction is a standard parameter, and usually the scanning mode includes a scanning mode corresponding to the standard parameter. If the number of subdivisions of the mode parameter is lower than the number of subdivisions of the standard parameter or the resolution of the mode parameter is higher than the resolution of the standard parameter, the above-mentioned fast mode scanning mode is adopted, and the rasterized image data is further transmitted to the data expansion unit to expand the rasterized image data to meet the control requirements of the graphic generator, and the expanded rasterized image data is converted and stored by the image data conversion storage unit, the image data conversion storage unit includes a plurality of subdivision storage units, each subdivision storage unit stores the data of a subdivided pixel block in a basic pixel unit, that is, the data of a row of subdivided pixel units whose number is equal to the subdivision value, and the storage space of the subdivision storage unit is not less than the storage space of the data amount of the subdivision number value corresponding to the standard parameter. When processing data whose subdivision number is less than the subdivision number determined by the inclination angle of the graphic generator, the data is first expanded to the maximum subdivision number data, and then converted and stored, without changing the data position, so as to facilitate the subsequent image stretching and framing processing. If the value of the mode parameter is equal to the value of the standard parameter, the above-mentioned fine mode scanning mode is adopted, and the rasterized graphic data is directly transmitted to the image data conversion storage unit for conversion and storage. The rasterized image data is processed by an image data framing processing unit to obtain a framed image corresponding to the graphic generator.

[0034] The laser direct writing system may switch between modes other than the fine mode and the fast mode. According to the value of the subdivision number, more modes may be included. For example, if the maximum subdivision number that the laser direct writing system can achieve is S, the modes of the laser direct writing system may include the S mode, the S / 2 mode, the S / 4 mode, or more modes S(1 / 2) may be included as needed. n The S mode uses the subdivision number S as the subdivision value of the basic pixel unit row and column direction, the S / 2 mode uses the subdivision number S / 2 as the subdivision value of the basic pixel unit row and column direction, and the S / 4 mode uses the subdivision number S / 4 as the subdivision value of the basic pixel unit row and column direction. Preferably, S, S / 2, S / 4, S(1 / 2)n All are integer values.

[0035] For the S / 2 mode, the data expansion unit performs one to four two-row and two-column expansion for the subdivided pixel units in the rasterized image. For the S / 4 mode, the data expansion unit performs one to sixteen four-row and four-column expansion for the subdivided pixel units in the rasterized image. For the S(1 / 2) mode, the data expansion unit performs one to sixteen four-row and four-column expansion for the subdivided pixel units in the rasterized image. n mode, the data expansion unit performs one to two operations on the subdivided pixel units in the rasterized image. 2n of 2 n Row 2 n Data expansion of the column.

Claims

1. A scanning method of a laser direct writing system, wherein the laser direct writing system comprises a pattern generator and a control system, Features: The control system includes a mode acquisition unit, through which different mode parameters are acquired, and the mode parameters are the subdivision number or resolution of the laser direct writing system; Perform rasterization operation on the vector graphics according to different mode parameters to obtain rasterized image data; When the number of subdivisions of the mode parameter is lower than the number of subdivisions determined by the inclination angle of the pattern generator relative to the scanning direction or the resolution of the mode parameter is higher than the resolution determined by the inclination angle of the pattern generator relative to the scanning direction, the vector graphics is divided into a plurality of basic pixel units, each basic pixel unit corresponds to a projection pixel unit of a pixel element of the pattern generator that is not tilted, each basic pixel unit is divided in the scanning direction and the sub-scanning direction according to the number of subdivisions to obtain subdivided pixel units, 0 or 1 is assigned to each subdivided pixel unit to obtain rasterized image data, and the subdivided pixel units of the rasterized graphic data are row-column expanded according to the actual number of subdivisions determined by the inclination angle of the pattern generator, the expanded data is the same as the corresponding subdivided pixel unit data, after the rasterization expansion, the number of rows and columns of the subdivided pixel units of the basic pixel unit is the same as the number of rows and columns of the subdivided pixel units of the basic pixel unit corresponding to the number of subdivisions determined by the inclination angle of the pattern generator relative to the scanning direction, which meets the control requirements of the pattern generator, and after the rasterization expansion, the rasterized data is converted and stored, and frame processing is performed based on the converted and stored rasterized data; When the subdivision number of the pattern parameter is equal to the subdivision number determined by the inclination angle of the graphic generator relative to the scanning direction or the resolution of the pattern parameter is equal to the resolution determined by the inclination angle of the graphic generator relative to the scanning direction, the vector graphics is divided into a plurality of basic pixel units, each basic pixel unit corresponds to a projection pixel unit of a pixel element of the graphic generator that is not tilted, each basic pixel unit is divided in the scanning direction and the sub-scanning direction according to the subdivision number to obtain subdivided pixel units, each subdivided pixel block is assigned a value of 0 or 1 to obtain rasterized image data, and then the rasterized data is converted and stored, and frame processing is performed based on the converted and stored rasterized data.

2. The scanning method of the laser direct writing system according to claim 1, Features: The difference between the different mode parameters is 2 n or (1 / 2) n multiple relationship.

3. The scanning method of the laser direct writing system according to claim 1, Features: The different mode parameters also include the number of subdivisions or the resolution determined according to the inclination angle of the pattern generator relative to the scanning direction.

4. The scanning method of the laser direct writing system according to claim 1, Features: For the number of subdivisions determined according to the inclination angle of the pattern generator relative to the scanning direction (1 / 2) n The data expansion is performed from one to two times for the subdivided pixel units in the rasterized image. 2n of 2 n Row 2 n The data of the column is expanded, wherein the subdivided pixel unit is the smallest pixel unit in the rasterized image obtained according to the mode parameters.

5. The scanning method of the laser direct writing system according to claim 1, Features: When rasterized data is converted and stored, the data is stored in a storage unit with the number of subdivisions determined by the inclination angle of the pattern generator relative to the scanning direction as the data amount, and the data stored in the storage unit constitutes a subdivided pixel block.

6. The scanning method of the laser direct writing system according to claim 5, Features: The storage space of the storage unit is greater than the data storage capacity of the subdivision number value determined according to the inclination angle of the pattern generator relative to the scanning direction.

7. A laser direct writing system using any scanning method of claims 1-6, comprising a pattern generator and a control system, Features: The control system includes a mode acquisition unit, a vector image rasterization unit, a data expansion unit, an image data conversion storage unit and an image data framing processing unit. The mode acquisition unit acquires mode parameters or mode instructions, and the mode instructions include mode parameters. The vector image rasterization unit acquires the mode parameters of the mode acquisition unit, and performs rasterization operation on the vector image according to the mode parameters to obtain rasterized image data. If the number of subdivisions indicated by the mode parameters is lower than the number of subdivisions obtained according to the inclination angle of the graphic generator relative to the scanning direction, the rasterized image data is transmitted to the data expansion unit to expand the rasterized image data. The expanded rasterized image data is converted and stored by the image data conversion storage unit. If the number of subdivisions indicated by the mode parameters is equal to the number of subdivisions obtained according to the inclination angle of the graphic generator relative to the scanning direction, the rasterized image data is directly transmitted to the image data conversion storage unit, the rasterized image data is converted and stored by the image data conversion storage unit, and the rasterized image data is processed by the image data framing processing unit to obtain a framed image corresponding to the graphic generator.

8. The laser direct writing system according to claim 7, Features: The image data conversion storage unit includes a plurality of subdivision storage units, wherein the storage space of the subdivision storage unit is not less than the storage space of the data amount of the subdivision number value obtained according to the inclination angle of the graphic generator relative to the scanning direction, and each subdivision storage unit stores the data of a subdivision pixel block in a basic pixel unit, wherein the basic pixel unit corresponds to a projection pixel unit of a pixel element of a graphic generator that is not tilted; and the subdivision pixel block is a row of subdivision pixel units in the basic pixel unit.

9. The laser direct writing system according to claim 1 or 7, Features: The pattern generator is a digital micromirror device.

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