Laser imaging system and laser imaging machine

Abstract

The invention provides a laser imaging system and a laser imager, and the system comprises a graph scanning module which comprises a laser scanner, an image sensor and a controller, and the controller comprises a gray value distribution calculation unit, an optical loss adjustment unit, an exposure parameter adjustment unit, a graph fusion unit and a graph optimization unit; the graph conversion module is used for converting the scanned graph data into machine data; the graphic imaging module comprises a laser emitter used for projecting machine data on a photosensitive material; the mechanical control module comprises a guide rail for driving the laser transmitter to move; according to the laser imaging system provided by the invention, proper laser performance can be selected when the graph is acquired, so that the effect of the graph is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser imaging, and particularly relates to a laser imaging system and a laser imaging machine. Background Art

[0002] Laser imaging technology refers to a technology in which a laser direct imaging device scans the pattern of an object. During the pattern formation process, a computer converts the graphic into machine data and transmits it to a digital micromirror device (DMD), and then directly projects the graphic onto a photosensitive material to complete the exposure.

[0003] In the prior art, when acquiring graphic data, noise will have a greater impact on the accuracy of the scanned image. While suppressing the noise, the performance of the laser itself will also be suppressed, and there will be brightness and darkness differences in the images captured by the image sensor after fusion due to the exposure time. It is very difficult to find a suitable laser performance between the fused images of single images. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide a laser imaging system, aiming to solve the technical problems mentioned in the background art.

[0005] In order to achieve the above purpose, the present invention is implemented by the following technical solutions:

[0006] A laser imaging system, comprising:

[0007] A graphic scanning module: including a laser scanner, an image sensor, and a controller. The controller includes a gray value distribution calculation unit, a light loss adjustment unit, an exposure parameter adjustment unit, a graphic fusion unit, and a graphic optimization unit;

[0008] A graphic conversion module: used to convert the scanned graphic data into machine data;

[0009] A graphic imaging module: including a laser emitter for projecting machine data onto a photosensitive material;

[0010] A mechanical control module: including a guide rail for driving the movement of the laser emitter;

[0011] The gray value distribution calculation unit is used for: determining the maximum light transmittance of the light loss element according to the ambient light in the environment to obtain a photoelectron-noise model, establishing a photoelectron-gray value curve, and determining the gray value distribution interval according to the photoelectron-noise model and the photoelectron-gray value curve;

[0012] The optical loss adjustment unit is configured to: preset an initial exposure time and a reference optical loss magnification, determine whether the gray value of the spot image under the current parameters is within the gray value distribution range, and optimize and adjust the reference optical loss magnification according to the determination result;

[0013] The exposure parameter adjustment unit is configured to: verify whether the updated gray value is within the gray value distribution range according to the optimized and adjusted reference optical loss magnification and the initial exposure time, and optimize and adjust the initial exposure time according to the verification result;

[0014] The graphic fusion unit is configured to: scan the object to be scanned by using the adjusted reference optical loss magnification and exposure time, sequentially obtain all scanned images, and obtain a fused gray image according to the pixel intensity values of the scanned images;

[0015] The graphic optimization unit is configured to: establish a gray mean - exposure time function according to the fused gray image, calculate a comprehensive verification parameter to determine whether the fused gray image is successfully verified, and if not, set additional scanned images to optimize the fused gray image to obtain graphic data.

[0016] According to one aspect of the above technical solution, the gray value distribution calculation unit is specifically configured to:

[0017] Obtain the ambient light in the image scanning environment, generate ambient noise, and establish a gray model to perform curve fitting on the gray value of the ambient noise and the light transmittance of the optical loss element;

[0018] Set the critical gray value of the ambient noise, and based on the gray model, obtain the maximum value of the light transmittance of the optical loss element corresponding to the critical gray value;

[0019] Under the condition of the maximum value of the light transmittance of the optical loss element, obtain the current ambient noise and the number of photoelectrons of the laser scanner, and establish a photoelectron - noise model to obtain the signal - to - noise ratio;

[0020] Preset a signal - to - noise ratio limit value, and find the gray value corresponding to the signal - to - noise ratio limit value in the photoelectron - noise model as the minimum gray value;

[0021] Establish a photoelectron - gray value curve, find a straight - line segment with a linear change law in the photoelectron - gray value curve, select the highest point of the straight - line segment as the maximum gray value, and use the range between the minimum gray value and the maximum gray value as the gray value distribution range.

[0022] According to one aspect of the above technical solution, the optical loss adjustment unit is specifically configured to:

[0023] Set the initial exposure time and the reference optical loss magnification;

[0024] Capture a spot image of the object to be scanned through the image sensor to obtain the initial gray value of the spot image;

[0025] Determine whether the maximum value of the initial gray value is within the gray value distribution range;

[0026] If not, optimize the reference light loss magnification through the light loss magnification optimization formula, make the laser pass through the optimized reference light loss magnification, calculate the updated gray value of the spot image, and record the final reference light loss magnification.

[0027] According to one aspect of the above technical solution, the exposure parameter adjustment unit is specifically used for:

[0028] Calculate the minimum change amount of the gray value of the spot image, and determine whether the minimum change amount of the gray value is within the gray value distribution range;

[0029] If so, the verification passes, and the final exposure time is recorded;

[0030] If not, optimize the exposure time through the exposure time optimization formula, expose the object to be scanned with the optimized exposure time, and record the final exposure time.

[0031] According to one aspect of the above technical solution, the graphic fusion unit is specifically used for:

[0032] Perform a secondary scan on the object to be scanned using the final reference light loss magnification and the final exposure time to obtain a scanned image;

[0033] Adjust the final reference light loss magnification and the final exposure time to sequentially obtain all scanned images of the object to be scanned;

[0034] Obtain the pixel intensity value of each scanned image, and through the irradiance conversion formula, obtain the fusion irradiance map of multiple scanned images, and map the fusion irradiance map into a fusion gray image.

[0035] According to one aspect of the above technical solution, the graphic optimization unit is specifically used for:

[0036] Obtain the regional gray mean value of each part in the fusion gray image, and fit the regional gray mean value with the exposure time used during the scan of the scanned image corresponding to this part to obtain a gray mean - exposure time function;

[0037] According to the grayscale mean-exposure time function, the verification index in the fused grayscale image is calculated to obtain a first verification parameter, and the number of problematic pixels in the fused grayscale image is found to obtain a second verification parameter;

[0038] The first verification parameter and the second verification parameter are integrated to obtain a comprehensive verification parameter.

[0039] According to one aspect of the above technical solution, the graphics optimization unit is further specifically used for:

[0040] Setting a verification threshold, and if the comprehensive verification parameter is less than the verification threshold, setting an additional scan image;

[0041] Selecting a first judgment formula according to the distribution of the number of problematic pixels in the fused grayscale image;

[0042] Selecting a second judgment formula according to the image description in the fused grayscale image;

[0043] Combining the first judgment formula and the second judgment formula to solve the optimal exposure time of the additional scanned image;

[0044] The additional scanned image is added and image fusion is performed again to obtain graphic data.

[0045] The present invention also provides a laser imaging machine, comprising the laser imaging system as described above.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] By sequentially adding a grayscale value distribution calculation unit, a light loss adjustment unit, an exposure parameter adjustment unit, a graphic fusion unit, and a graphic optimization unit to the graphic scanning module, after the laser scanner irradiates the object to be scanned, through the grayscale value distribution calculation unit, after determining the grayscale value distribution range, then through the light loss adjustment unit, preset the initial exposure time and the reference light loss magnification, and adjust the reference light loss magnification according to the grayscale value of the spot image of the object to be scanned; then through the exposure parameter adjustment unit, verify the updated grayscale value of the spot image to optimize and adjust the initial exposure time. The above steps can determine the optimal reference light loss magnification and exposure time of a single image, achieving a better balance between noise and graphic performance parameters; then through the graphic fusion unit, fuse all scanned images and establish a grayscale mean-exposure time function to obtain comprehensive verification parameters, and then optimize the fused grayscale image according to the verification results to obtain graphic data; finally, through the graphic conversion module, convert the scanned graphic data into machine data, then through the graphic imaging module, transmit the machine data to the digital micromirror array, and drive the laser emitter to project the graphic on the photosensitive material through the guide rail in the mechanical control module to complete direct imaging.

[0048] The present invention can select appropriate laser performance during graphic acquisition, thereby improving the graphic effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a structural block diagram of the laser imaging system in the first embodiment of the present invention;

[0050] Figure 2 is Figure 1 a flowchart of each unit in the controller in

[0051] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. SPECIFIC EMBODIMENTS

[0052] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0053] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there can also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0055] Please refer to Figure 1-2 , which shows a laser imaging system in the first embodiment of the present invention, characterized by comprising:

[0056] Graphic scanning module 10: Comprising a laser scanner, an image sensor, and a controller, the controller includes a grayscale value distribution calculation unit, a light loss adjustment unit, an exposure parameter adjustment unit, a graphic fusion unit, and a graphic optimization unit;

[0057] Graphic conversion module 20: Used to convert the scanned graphic data into machine data;

[0058] Graphic imaging module 30: Comprising a laser emitter for projecting machine data onto a photosensitive material;

[0059] Mechanical control module 40: Comprising a guide rail for driving the movement of the laser emitter;

[0060] The grayscale value distribution calculation unit is used for: determining the maximum light transmittance of the light loss element according to the ambient light in the current environment to obtain a photoelectron-noise model, establishing a photoelectron-grayscale value curve, and determining the grayscale value distribution interval according to the photoelectron-noise model and the photoelectron-grayscale value curve;

[0061] The light loss adjustment unit is used for: presetting an initial exposure time and a reference light loss magnification to determine whether the grayscale value of the spot image under the current parameters is within the grayscale value distribution interval, and optimizing and adjusting the reference light loss magnification according to the judgment result;

[0062] The exposure parameter adjustment unit is used for: verifying whether the updated grayscale value is within the grayscale value distribution interval according to the optimized and adjusted reference light loss magnification and the initial exposure time, and optimizing and adjusting the initial exposure time according to the verification result;

[0063] The graphic fusion unit is used for: scanning the object to be scanned by using the adjusted reference light loss magnification and exposure time, sequentially obtaining all scanned images, and obtaining a fused grayscale image according to the pixel intensity values of the scanned images;

[0064] The graphic optimization unit is used to: establish a grayscale mean-exposure time function based on the fused grayscale image, calculate a comprehensive verification parameter to determine whether the fused grayscale image is successfully verified, and if not, set additional scanned images to optimize the fused grayscale image to obtain graphic data.

[0065] It can be understood that in the present invention, by sequentially adding a grayscale value distribution calculation unit, a light loss adjustment unit, an exposure parameter adjustment unit, a graphic fusion unit, and a graphic optimization unit in the graphic scanning module, after the laser scanner irradiates the object to be scanned and passes through the grayscale value distribution calculation unit to determine the grayscale value distribution range, then through the light loss adjustment unit, the initial exposure time and the reference light loss magnification are preset, and the reference light loss magnification is adjusted according to the grayscale value of the spot image of the object to be scanned; then through the exposure parameter adjustment unit, the updated grayscale value of the spot image is verified to optimize and adjust the initial exposure time. The above steps can determine the optimal reference light loss magnification and exposure time of a single image, achieving a better balance between noise and graphic performance parameters; then through the graphic fusion unit, all scanned images are fused, and a grayscale mean-exposure time function is established to obtain a comprehensive verification parameter, and then the fused grayscale image is optimized according to the verification result to obtain graphic data; finally, the scanned graphic data is converted into machine data through the graphic conversion module, and then the machine data is transmitted to the digital micromirror array through the graphic imaging module, and the laser emitter is driven by the guide rail in the mechanical control module to project the graphic on the photosensitive material to complete direct imaging.

[0066] The present invention can select appropriate laser performance during graphic acquisition, thereby improving the graphic effect.

[0067] It should be noted that the light loss element is used to weaken the intensity of the laser according to requirements to improve the image quality.

[0068] Specifically, in this embodiment, the helium-neon laser is used for the laser scanner, and the CCD camera is used for the image sensor.

[0069] Further, the grayscale value distribution calculation unit is specifically used to:

[0070] Obtain the ambient light in the image scanning environment, generate ambient noise, and establish a grayscale model to perform curve fitting on the grayscale value of the ambient noise and the light transmittance of the light loss element;

[0071] The expression of the grayscale model is as follows:

[0072]

[0073] Among them, U represents the current grayscale value reflected by the image sensor under the current ambient noise, q e$N$ represents the number of photons of ambient light, $C$ represents the light transmittance of the light loss element, $T$ represents the exposure time, $\mu$ represents the quantum efficiency, $G_a$ represents the gain of the image sensor, and $O_f$ represents the bias of the image sensor;

[0074] Set the critical gray value of the ambient noise, and based on the gray model, to obtain the maximum value of the light transmittance of the light loss element corresponding to the critical gray value;

[0075] The calculation formula of the critical gray value is as follows:

[0076]

[0077] Among them, $U$ l represents the critical gray value, $i$ and $j$ represent the coordinate points of the image, and $m$ and $n$ represent the total number of coordinate points;

[0078] Under the condition of the maximum value of the light transmittance of the light loss element, obtain the current ambient noise and the number of photoelectrons of the laser scanner, and establish a photoelectron-noise model to obtain the signal-to-noise ratio;

[0079] The expression of the photoelectron-noise model is:

[0080]

[0081] $S$ represents the number of photoelectrons reflected on the image sensor, and $N$ represents the ambient noise;

[0082] Preset the signal-to-noise ratio limit value, and find the gray value corresponding to the signal-to-noise ratio limit value from the photoelectron-noise model as the minimum gray value $U$ min ;

[0083] Establish a photoelectron-gray value curve, find the straight line segment that changes linearly in the photoelectron-gray value curve, and select the highest point of the straight line segment as the maximum gray value $U$ max , and use the range of the minimum gray value and the maximum gray value as the gray value distribution interval.

[0084] It can be understood that before obtaining an image by laser scanning, the ambient noise is first determined according to the ambient light in the current environment, and then the light transmittance of the light loss element is adjusted to obtain a fitting curve between the gray value generated by the ambient noise and the light transmittance of the light loss element for the image sensor. By setting a critical gray value, the maximum value of the light transmittance of the light loss element is obtained. Since the light transmittance of the light loss element cannot be too small to suppress the ambient noise, otherwise it will affect the transmittance of the laser during subsequent laser scanning. Then, the object to be scanned can be scanned by a laser scanner. A photoelectron-noise model is established based on the number of photoelectrons emitted by the laser scanner and the current ambient noise to obtain the signal-to-noise ratio. Then, a signal-to-noise ratio limit value (a parameter set by humans to ensure that the accuracy of the subsequent spot image is within an acceptable range) is set, and the number of photoelectrons corresponding to this signal-to-noise ratio limit value is found in the photoelectron-noise model. The gray value corresponding to the spot image in the image sensor when the laser scanner emits this number of photoelectrons is found from the image sensor to obtain the minimum gray value. Since there is a relationship between the number of photoelectrons emitted by the laser scanner and the gray value of the spot image in the image sensor, a photoelectron-gray value curve is established to describe their relationship. Since the two have a linear segment and a non-linear segment, to ensure the stability of laser detection, the linear segment needs to be found, and the maximum gray value in the linear segment is used as the maximum gray value. The range between the minimum gray value and the maximum gray value is used as the gray value distribution interval. When scanning the image subsequently, the gray value of the spot image needs to be within this range to improve the effect of laser scanning.

[0085] Further, the light loss adjustment unit is specifically configured to:

[0086] Set an initial exposure time and a reference light loss magnification;

[0087] Capture the spot image of the object to be scanned through the image sensor to obtain the initial gray value of the spot image;

[0088] Determine whether the maximum value of the initial gray value is within the gray value distribution interval;

[0089] If not, optimize the reference light loss magnification through the light loss magnification optimization formula, allow the laser to pass through the optimized reference light loss magnification, calculate the updated gray value of the spot image, and record the final reference light loss magnification;

[0090] The light loss magnification optimization formula is as follows:

[0091]

[0092] where ΔCi represents the change amount of the reference light loss magnification, and U x represents the maximum gray value of the spot image;

[0093] It is understandable that an initial exposure time and a reference light loss magnification are set. Under these parameters, when the object is scanned by the laser scanner, the image sensor can capture the spot image, and then obtain the initial gray value of the spot image. Compare the maximum value of the initial gray value with the gray value distribution interval obtained in the gray value distribution calculation unit. If it is within the gray value distribution interval, it can indicate that the preset exposure time and reference light loss magnification are correct. Record the exposure time and reference light loss magnification and then proceed to the next step. If it is not within the gray value distribution interval, first do not change the exposure time, adjust the reference light loss magnification through the light loss magnification optimization formula, then calculate the gray value of the spot image using the optimized reference light loss magnification, and record the final reference light loss magnification. It should be noted that the light loss element can be a mechanical optical attenuator or an electro-optical attenuator.

[0094] Further, the exposure parameter adjustment unit is specifically configured to:

[0095] Calculate the minimum change amount of the gray value of the spot image, and determine whether the minimum change amount of the gray value is within the gray value distribution interval;

[0096] The formula for calculating the minimum change amount of the gray value is:

[0097] ΔUi min =U max (1 - 10 -ΔCimin );

[0098] Where ΔUi min represents the minimum change amount of the gray value, and ΔCimin represents the minimum value of the reference light loss magnification;

[0099] If so, the verification passes, and the final exposure time is recorded;

[0100] If not, optimize the exposure time through the exposure time optimization formula, expose the object to be scanned using the optimized exposure time, and record the final exposure time;

[0101] The exposure time optimization formula is:

[0102]

[0103] Where, ΔT represents the change amount of the exposure time, and T i represents the exposure time during this scan;

[0104] It can be understood that the spot image not only needs to meet the requirements of the gray value distribution, but also needs to consider the minimum change amount of the gray value. Because sometimes, just adjusting the reference light loss magnification still cannot make the gray value meet the gray value distribution interval. And due to the existence of the maximum transmittance of the light loss element, sometimes if you want to meet the gray value distribution interval, after adjusting the reference light loss magnification, the transmittance may be greater than the maximum transmittance of the light loss element. Therefore, it is necessary to verify whether the minimum change amount of the gray value is still within the gray value distribution interval. If so, the final exposure time is determined. If not, the exposure time is optimized through the exposure time optimization formula, and the updated gray value is recalculated with the optimized exposure time, and the final exposure time and the updated gray value are recorded. The above steps complete the adjustment of the reference light loss magnification and the exposure time of a single image.

[0105] Further, the graphic fusion unit is specifically used for:

[0106] Performing a secondary scan on the object to be scanned using the final reference light loss magnification and the final exposure time to obtain a scanned image;

[0107] Adjusting the final reference light loss magnification and the final exposure time to sequentially obtain all scanned images of the object to be scanned;

[0108] Obtaining the pixel intensity value of each scanned image, and through the irradiance conversion formula, obtaining a fused irradiance map of multiple scanned images, and mapping the fused irradiance map into a fused gray image;

[0109] The irradiance conversion formula is:

[0110]

[0111] Where, θ represents the pixel intensity value of the scanned image, y represents the weight, i represents the pixel point position in the scanned image, j represents the serial number of the scanned image, R represents the total number of scanned images, N i represents the irradiance, t j represents the exposure time of the scanned image j, and g represents the logarithmic function;

[0112] It can be understood that since the ambient noise of each scanned image is different and the spot images during scanning are also different, for each image, it is necessary to select the transmittance of the appropriate light loss element and the exposure time according to the gray value distribution calculation unit, the light loss adjustment unit, and the exposure parameter adjustment unit, and obtain the pixel intensity value of each scanned image under this parameter. Then, multiple scanned images are fused, and the fused irradiance map is obtained through the irradiance conversion formula. Subsequently, the irradiance of the fused scanned image is represented according to the pixel intensity value. Finally, the fused irradiance map is mapped into a fused grayscale image through tone mapping.

[0113] Further, the graphic optimization unit is specifically used for:

[0114] Obtain the regional gray mean value of each part in the fused grayscale image, and fit the regional gray mean value with the exposure time used during the scanning of the scanned image corresponding to this part to obtain a gray mean - exposure time function;

[0115] The gray mean - exposure time function is:

[0116]

[0117] where, represents the gray mean value, α represents the slope, and b represents the intercept;

[0118] According to the gray mean - exposure time function, calculate the verification index in the fused grayscale image to obtain the first verification parameter, and find the number of problem pixel points in the fused grayscale image to obtain the second verification parameter;

[0119] Fuse the first verification parameter and the second verification parameter to obtain a comprehensive verification parameter;

[0120] The calculation formula for the first verification parameter is:

[0121]

[0122] where, P S represents the range of the gray mean value in the fused grayscale image, P m represents the average value of the gray mean values of each part in the fused grayscale image, and p δ represents the mean square deviation of the gray mean value in the fused grayscale image; it should be noted that these three indicators are all the results after normalization;

[0123] The calculation formula for the second verification parameter is:

[0124]

[0125] Among them, V1 represents the number of overexposed pixel points, V2 represents the number of underexposed pixel points, and V represents the number of all pixel points;

[0126] The comprehensive verification parameter calculation formula is:

[0127]

[0128] Set a verification threshold (0.95 in this embodiment). If the comprehensive verification parameter is less than the verification threshold, set an additional scanned image;

[0129] Select a first judgment formula according to the quantity distribution of problem pixel points in the fused grayscale image;

[0130] Select a second judgment formula according to the image description in the fused grayscale image;

[0131] Simultaneously solve the first judgment formula and the second judgment formula to obtain the optimal exposure time of the additional scanned image;

[0132] The first judgment formula is:

[0133]

[0134] The second judgment formula is:

[0135] t R+1 =t k +(R + 1 - k)Δt;

[0136] Among them, t R represents the exposure time of the last scanned image, t R+1 represents the exposure time of the additional scanned image, t1 represents the exposure time of the first scanned image, Δt represents the exposure time change amount of the additional scanned image, k represents the serial number of the scanned image with the best exposure effect, t k represents the exposure time of the k image, and the calculation formula of k is as follows:

[0137]

[0138] Add the additional scanned image and re - perform image fusion to obtain graphic data.

[0139] It can be understood that the fused grayscale image can reflect the grayscale mean values of various parts of the fused scanned image. For each part of the fused scanned image, a corresponding single scanned image can be found. By fitting the grayscale mean value of each part with the exposure time (previously calculated) of the corresponding scanned image, a grayscale mean value - exposure time function can be obtained, and then the relationship between the grayscale mean value and the exposure time can be obtained. Then, in the grayscale mean value - exposure time function, find the full range, average value, and mean square deviation of the pixel points of the fused grayscale image to calculate the first verification parameter. Then, find the number of overexposed points and underexposed points in the fused grayscale image, and calculate the second verification parameter. Based on these, a comprehensive verification parameter is fused. Determine whether the quality of the fused scanned image meets the standard according to the comprehensive verification parameter. If not, an additional scanned image with a higher or lower exposure needs to be added according to the above method to balance the quality of the fused scanned image. Add the additional scanned image and perform image fusion again to obtain graphic data, which is used as the machine data for subsequent laser development.

[0140] Finally, the scanned graphic data is converted into machine data through the graphic conversion module, and then the machine data is transmitted to the digital micromirror array through the graphic imaging module. Through the guide rail in the mechanical control module, the laser emitter is driven to project the graphic onto the photosensitive material to complete direct imaging.

[0141] In summary, the laser imaging system in the above embodiments of the present invention can select appropriate laser performance when acquiring graphics, thereby improving the effect of the graphics.

[0142] The second embodiment of the present invention provides a laser imaging machine, including the laser imaging system mentioned in the first embodiment.

[0143] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0144] The above embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. A laser imaging system, characterized in that, Including: Graphic scanning module: including a laser scanner, an image sensor, and a controller, the controller includes a grayscale value distribution calculation unit, a light loss adjustment unit, an exposure parameter adjustment unit, a graphic fusion unit, and a graphic optimization unit; Graphic conversion module: used to convert the scanned graphic data into machine data; Graphic imaging module: including a laser emitter for projecting machine data onto a photosensitive material; Mechanical control module: including a guide rail for driving the movement of the laser emitter; The grayscale value distribution calculation unit is used to: determine the maximum light transmittance of the light loss element according to the ambient light in the current environment, so as to obtain a photoelectron-noise model, establish a photoelectron-grayscale value curve, and determine the grayscale value distribution interval according to the photoelectron-noise model and the photoelectron-grayscale value curve; The light loss adjustment unit is used to: preset an initial exposure time and a reference light loss magnification, so as to judge whether the grayscale value of the spot image under the current parameters is within the grayscale value distribution interval, and optimize and adjust the reference light loss magnification according to the judgment result; The exposure parameter adjustment unit is used to: verify whether the updated grayscale value is within the grayscale value distribution interval according to the optimized reference light loss magnification and the initial exposure time, and optimize and adjust the initial exposure time according to the verification result; The graphic fusion unit is used to: scan the object to be scanned by using the adjusted reference light loss magnification and exposure time, sequentially obtain all scanned images, and obtain a fused grayscale image according to the pixel intensity values of the scanned images; The graphic optimization unit is used to: establish a grayscale mean-exposure time function according to the fused grayscale image, calculate a comprehensive verification parameter, so as to judge whether the fused grayscale image is successfully verified, and if not, set additional scanned images to optimize the fused grayscale image to obtain graphic data.

2. The laser imaging system according to claim 1, characterized in that, Specifically, the grayscale value distribution calculation unit is used to: Obtain the ambient light in the image scanning environment, generate ambient noise, and establish a grayscale model to perform curve fitting on the grayscale value of the ambient noise and the light transmittance of the light loss element; Set the critical grayscale value of the ambient noise, and based on the grayscale model, obtain the maximum light transmittance of the light loss element corresponding to the critical grayscale value; Under the condition of the maximum light transmittance of the light loss element, obtain the current ambient noise and the number of photoelectrons of the laser scanner, establish a photoelectron-noise model to obtain the signal-to-noise ratio; Preset a signal-to-noise ratio limit value, and find the grayscale value corresponding to the signal-to-noise ratio limit value in the photoelectron-noise model as the grayscale minimum value; Establish a photoelectron-grayscale value curve, find a straight line segment with a linear change law in the photoelectron-grayscale value curve, select the highest point of the straight line segment as the grayscale maximum value, and use the range of the grayscale minimum value and the grayscale maximum value as the grayscale value distribution interval.

3. The laser imaging system according to claim 2, wherein Specifically, the light loss adjustment unit is used to: Set an initial exposure time and a reference light loss magnification; Capture the spot image of the object to be scanned through the image sensor to obtain the initial grayscale value of the spot image; Determine whether the maximum value of the initial grayscale value is within the grayscale value distribution interval; Otherwise, the reference light loss ratio is optimized by using a light loss ratio optimization formula, and the laser is passed through the optimized reference light loss ratio, the updated gray value of the light spot image is calculated, and the final reference light loss ratio is recorded.

4. The laser imaging system according to claim 3, wherein The exposure parameter adjustment unit is specifically used for: Calculating the minimum change amount of the gray value of the spot image, and determining whether the minimum change amount of the gray value is within the gray value distribution interval; If yes, the verification is passed and the final exposure time is recorded; If not, the exposure time is optimized by the exposure time optimization formula, and the scanned object is exposed using the optimized exposure time, and the final exposure time is recorded.

5. The laser imaging system according to claim 4, wherein The graphics fusion unit is specifically used for: Performing a second scan on the object to be scanned using the final reference light loss magnification and the final exposure time to obtain a scanned image; Adjusting the final reference light loss magnification and the final exposure time to sequentially acquire all scanned images of the object to be scanned; The pixel intensity value of each scanned image is obtained, and a fused radiation illumination map of the plurality of scanned images is obtained through a radiation illumination conversion formula, and the fused radiation illumination map is mapped into a fused grayscale image.

6. The bracket according to claim 5, characterized in that, The graphics optimization unit is specifically used for: Obtaining a regional grayscale mean value of each part in the fused grayscale image, and fitting the regional grayscale mean value with the exposure time used when scanning the scanned image corresponding to the part, to obtain a grayscale mean value-exposure time function; According to the grayscale mean-exposure time function, the verification index in the fused grayscale image is calculated to obtain a first verification parameter, and the number of problematic pixels in the fused grayscale image is found to obtain a second verification parameter; The first verification parameter and the second verification parameter are integrated to obtain a comprehensive verification parameter.

7. The laser imaging system according to claim 6, wherein The graphics optimization unit is also specifically used for: Setting a verification threshold, and if the comprehensive verification parameter is less than the verification threshold, setting an additional scan image; Selecting a first judgment formula according to the distribution of the number of problematic pixels in the fused grayscale image; Selecting a second judgment formula according to the image description in the fused grayscale image; Combining the first judgment formula and the second judgment formula to solve the optimal exposure time of the additional scanned image; The additional scanned image is added and image fusion is performed again to obtain graphic data.

8. A laser imaging machine, characterized in that, A laser imaging system comprising any one of claims 1 to 7.

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