An efficient data processing method for DMD tilt scanning

Abstract

The present invention relates to the field of laser direct writing exposure technology, specifically to an efficient data processing method for DMD tilt scanning. The present invention adopts a combination of a host server, a SPIE data processing module, a high-speed transmission module and a data processing module to complete the efficient processing of image data, and utilizes the advantages of synchronous calculation of vector diagrams of the host server to complete the simulation transformation, tilt and strip cutting required by multiple DMDs of the image, and sends multiple strip vector diagrams to the SPIE data processing module for rasterization synchronization processing. The rasterized data is contour compressed and transmitted to the data processing module by the high-speed transmission module. The data processing module performs time-sharing synchronization operation when receiving data, realizes data zero filling, contour filling, point extraction merging, burst storage zero filling, mixed insertion, etc., and finally performs frame processing, displays the data on the DMD, and realizes the high-speed tilt scanning function. The present invention can process graphic data faster, so that high resolution matches high production capacity.

Description

Technical Field

[0001] The invention relates to the technical field of laser direct writing exposure, in particular to a high-efficiency data processing method for DMD tilt scanning. Background Art

[0002] Printed circuit boards are the mother of current electronic products. One of the most important processes in its manufacturing process is circuit exposure, which determines the yield rate and line width accuracy of the circuit board. As consumer electronic products become lighter and lighter, the line width and line spacing of circuit boards are getting thinner and thinner. Especially in the field of flexible circuit boards, the film expansion and contraction in the traditional exposure process has seriously restricted the quality of flexible circuit boards, resulting in the rapid recognition of the laser direct imaging process.

[0003] At present, laser direct imaging equipment mainly uses TI's DLP solution, which is similar to a traditional projector. It directly images the required circuit on the target surface and can achieve synchronous expansion and contraction with the substrate. In order to pursue higher resolution of the process, the DMD is usually tilted so that the single pixel is partially overlapped in the vertical direction of the scan. Tilt scanning reduces the grid accuracy in disguise (improves the resolution accuracy), but it will bring a larger amount of data, affect the efficiency of laser direct imaging exposure, and is not conducive to the industrialization of this technology in the circuit board field. Summary of the invention

[0004] The present invention proposes an efficient processing method for DMD tilt scanning, which utilizes the advantages of host multi-core chips, SPIE expansion, etc., and puts data into a synchronous processing mode as much as possible, making the underlying FPGA driving the DMD to process data simply and reliably, thereby realizing the function of DMD high-speed scanning exposure.

[0005] To achieve the above object, the present invention provides the following technical solution: an efficient data processing method for DMD tilt scanning, comprising a host server, a SPIE data processing module, a high-speed transmission module and a data processing module, characterized in that:

[0006] The host server reads the vector map into the memory, and uses the host's advantage in floating-point number operations to perform affine transformation, tilting and strip segmentation operations on the vector map. The affine transformation can achieve operations such as expansion, contraction, and rotation, and the strip segmentation is to meet the requirements of synchronous scanning of multiple DMDs;

[0007] The SPIE data processing module is inserted into the SPIE slot of the host server. Each SPIE data processing module can carry multiple DMD terminals, which are connected by a high-speed transmission module. The SPIE data processing module performs sub-region segmentation, rasterization, contour compression, data transmission and other operations on the segmented strips. These operations can be synchronized in time sharing.

[0008] The rasterization process is divided into scanning direction and stepping direction analysis. The scanning direction analysis dpi is determined by the minimum resolution multiple of the scanning axis motion feedback; the stepping direction analysis dpi is determined by the lens magnification and the subdivision factor. n Decide;

[0009] After receiving the contour compressed data, the data processing module performs synchronous padding and bilateral zero padding. The padding process starts with filling each row of data with 0. Contour compression defines the flip position information, and the filling can be changed to 0 or 1 according to the flip position information. Then, operations such as sampling, mixed insertion, and burst storage zero padding are performed, so that the data chain is synchronized from data rasterization to the final data storage in DDR, which meets the data volume requirements of existing oblique scanning;

[0010] The sampling point merging and mixing operation refers to the subdivision factor n The stepping direction of the DMD point is subdivided under the decision of n It is necessary to sample and extract values ​​for each DMD point and combine these values ​​together to facilitate the subsequent framing processing;

[0011] The burst storage zero padding means that the length of each row of data matches the single storage length of DDR, so as to achieve the purpose of high-speed storage / reading;

[0012] The framing process refers to using FPGA to read the continuous address data of DDR according to the number of rows N required by DMD. The number of rows N must be a subdivision factor. n Multiples of, each row of data corresponds to a different DMD row number, requiring a different intercepted data starting address, the offset is every n When the row changes by 1 bit, all row data are intercepted to form a frame of graphics and transmitted to the DMD driver chip. The framing instruction is determined according to the position feedback of the scanning axis, that is, framing is started once every multiple of the rasterization accuracy in the scanning direction to complete the entire high-speed scanning process.

[0013] The high-speed transmission module can use USB 3.0, Gigabit Ethernet or 10 Gigabit fiber optic network port, depending on the actual data volume and cost of the system.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The invention provides a method for efficiently processing data of DMD tilt scanning, which uses a combination of a host server, a SPIE data processing module, a high-speed transmission module and a data processing module to efficiently process image data, utilizes the advantages of synchronous calculation of vector diagrams of the host server to complete the simulation transformation, tilting and strip cutting required by multiple DMDs, and sends multiple strip vector diagrams to the SPIE data processing module for rasterization synchronization processing. The rasterized data is contour compressed and transmitted to the data processing module by the high-speed transmission module. The data processing module performs time-sharing synchronization operation when receiving data, realizes data zero filling, contour filling, point merging, burst storage zero filling, mixed insertion, etc., and finally performs frame processing, displays the data on the DMD, and realizes the high-speed tilt scanning function. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an overall flow chart of the data tilt processing of the present invention;

[0017] Figure 2 It is a schematic diagram of the tilt scanning of the present invention;

[0018] Figure 3 is a diagram showing the relationship between the DMD tilt and the image tilt of the present invention;

[0019] Figure 4 A schematic diagram of the time-sharing synchronization operation of rasterizing graphics to storage according to the present invention;

[0020] Figure 5 It is a schematic diagram of the parallel reorganization arrangement of the present invention;

[0021] Figure 6 It is a schematic diagram of the framing process of the present invention; DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0023] The present invention proposes an efficient data processing method for DMD tilt scanning. In order to achieve high exposure accuracy, the exposure pattern can be decomposed into scanning direction and stepping direction resolution. The resolution in the scanning direction is determined by the minimum resolution multiple of the scanning axis motion feedback; the resolution in the stepping direction is determined by the DMD single point size and the lens magnification, and the tilt scanning can subdivide the DMD single point, further improving the resolution in the stepping direction. The tilt angle of the tilt scanning is A With subdivision factor n about, that is A =arctan(1 / n ).

[0024] The present invention utilizes the advantages of synchronous calculation of vector graphics of the host server to complete the simulation transformation, tilting and strip cutting required by multiple DMDs, and sends multiple strip vector graphics to the SPIE data processing module for rasterization synchronization processing. The rasterized data is contour compressed and transmitted to the data processing module by the high-speed transmission module. The data processing module performs time-sharing synchronization operation when receiving data, realizes data zero filling, contour filling, point merging, burst storage zero filling, mixed insertion, etc., and finally performs frame processing, displays the data on the DMD, and realizes the high-speed tilt scanning function.

[0025] In the example n =4 drawing. After the DMD is tilted, a triangular area will be formed on each side in the stepping direction. Because of the need for multiple DMD exposure splicing, the triangular area does not need to emit light, that is, the DMD is in the off state in the triangular area (the bitmap has a value of 0 in this area). In order to achieve efficient processing, all zero-filling operations here are delegated to the data processing module for execution. The rasterized bitmap presents a group of 4 columns under the influence of the subdivision factor. According to the position of the DMD single point, it is necessary to extract points in the bitmap. The DMD single point can be understood as a combination of 4 pixel points in the stepping direction of the figure, because the tilt effect in the scanning direction can be equivalent to arranging all points in a row. The effective area is 2 rows of points, and the triangular area is 1 row of points. In order to achieve requirements such as exposure uniformity, the triangular area should not be exposed, that is, 4 columns of zero-filling operations.

[0026] The effective DMD ranks are H × L , according to the subdivision factor n After tilting, the subdivision rows and columns are TH × TL , TH =( H -1)× n + L , TL =( L -1)× n + H Invalid number of columns for triangle area InL = H - n According to the total number of columns and the number of invalid columns, the total number of columns required for a single DMD can be determined, and then the width of the stripe segmentation can be determined.

[0027] The tilt occurs in the scanning direction. For scanning exposure, the bitmaps before and after the tilt can be equivalent, so the graphic tilt operation is performed in the vector map with less data. According to the transformation matrix obtained by alignment, the vector map is affine transformed in the host server, and then the vector map is striped according to the effective column width of each DMD to prepare the tilt angle in the scanning direction. AThe segmented and tilted strip vector graph is sent to the corresponding SPIE data processing module for rasterization.

[0028] The time-sharing synchronization model from rasterization to storage in DDR, i.e., strip region cutting → rasterization → contour compression → high-speed transmission → parsing and packetization → zero padding → point merging → interpolation → burst storage zero padding → storage in DDR. Each step is in a synchronous operation state after the first execution, i.e., the previous region bitmap is being transmitted at high speed, and the next strip region cutting is already being executed. The time-sharing synchronization steps are designed to be consistent in time planning, so that the time from the end of all rasterization to the storage of the last region bitmap in DDR can be controlled within 0.01s, realizing the front end of efficient processing of tilt scanning, such as Figure 5 shown.

[0029] Finally, according to the position feedback pulse of the scanning axis, the data processing module will perform frame processing, that is, form a frame of graphics required at the moment and transmit it to the DMD driver chip, such as Figure 6 The specific method of reading data is as follows:

[0030] ) The initial address of the first row of the first frame is D 0 , the intercept length is L

[0031] ) The first frame i The initial address of the row is D 0 +floor( i / 4)-1

[0032] …

[0033] The initial address of the first row of the jth frame is D 0 +( j -1) n · N a , N a The length of each line of graphics after zero padding when stored in DDR. The intercepted length is L

[0034] The initial address of the i-th row of the j-th frame is D 0 +( j -1) n · N a + floor( i / 4)-1.

Claims

1. An efficient data processing method for DMD tilt scanning, comprising a host server, a SPIE data processing module, a high-speed transmission module and a data processing module, characterized in that: The host server reads the vector map into the memory, and uses the host's advantage in floating-point number operations to perform affine transformation, tilting and strip segmentation operations on the vector map. The affine transformation can achieve expansion, contraction and rotation operations, and the strip segmentation is to meet the requirements of synchronous scanning of multiple DMDs; The SPIE data processing module is inserted into the SPIE slot of the host server. Each SPIE data processing module can carry multiple DMD terminals connected by a high-speed transmission module. The SPIE data processing module performs sub-region segmentation, rasterization, contour compression, and data transmission operations on the segmented strips. These operations can be synchronized in time sharing. The rasterization process is divided into scanning direction and stepping direction analysis. The scanning direction analysis dpi is determined by the minimum resolution multiple of the scanning axis motion feedback; the stepping direction analysis dpi is determined by the lens magnification and the subdivision factor. n Decide; After receiving the contour compressed data, the data processing module performs synchronous padding and bilateral zero padding. The padding process starts with filling each row of data with 0. Contour compression defines the flip position information, and the filling can be changed to 0 or 1 according to the flip position information. Then, sampling, mixed insertion, and burst storage zero padding operations are performed, so that the data chain is synchronized from data rasterization to the final data storage in DDR, which meets the data volume requirements of existing oblique scanning; The sampling and merging operations refer to the subdivision factor n The stepping direction of the DMD point is subdivided under the decision of n It is necessary to sample and extract values ​​for each DMD point and combine these values ​​together to facilitate the subsequent framing processing; The burst storage zero padding means that the length of each row of data matches the single storage length of DDR, so as to achieve the purpose of high-speed storage / reading; The framing process refers to using FPGA to read the continuous address data of DDR according to the number of rows N required by DMD. The number of rows N must be a subdivision factor. n Multiples of, each row of data corresponds to a different DMD row number, requiring a different intercepted data starting address, the offset is every n When the row changes by 1 bit, all row data are intercepted to form a frame of graphics and transmitted to the DMD driver chip. The framing instruction is determined according to the position feedback of the scanning axis, that is, framing is started once every multiple of the rasterization accuracy in the scanning direction to complete the entire high-speed scanning process.

2. The efficient data processing method for DMD tilt scanning according to claim 1, characterized in that: The high-speed transmission module can use USB 3.0, Gigabit Ethernet or 10 Gigabit fiber optic network port, depending on the actual data volume and cost of the system.

Images