CN222867000U - Automatic focusing device of high-precision projection exposure machine - Google Patents

Abstract

The utility model provides an automatic focusing device of a high-precision projection exposure machine, which comprises a projection module, a light splitting module, an electric displacement platform, an image detector and a main control module, wherein the light splitting module divides a focusing projection image emitted by the projection module into a first image and a second image with the same definition, the image detector is positioned on a propagation path of the first image, a target surface to be projected is positioned on the propagation path of the second image, an image acquisition port is used for receiving the first image acquired by the image detector, a distance control port is used for controlling the electric displacement platform to drive the projection module to move along a first direction when the definition of the first image does not meet the preset definition requirement until the precision of the first image meets the preset definition requirement, and the technical scheme is used for adjusting the focal length through focusing projection image definition, so that the adjustment accuracy is increased while an adjustment system is simplified, and meanwhile, the light splitting module is used for separating a path of research from a projection image, so that the operation is more convenient.

Description

Automatic focusing device of high-precision projection exposure machine

Technical Field

The embodiment of the utility model relates to the technical field of automatic focusing, in particular to an automatic focusing device of a high-precision projection exposure machine.

Background

How clearly the picture of the projection exposure machine is presented in front of the eyes of people is the basis for exerting the performance of the projection exposure machine. The acquisition of clear images is the basis for further processing and analysis of the images, and the accuracy of the whole exposure writing system is directly affected. Factors which restrict the definition of imaging are many, such as noise interference of illumination condition, geometric shape and distortion of scenery, physical characteristics of surface, characteristics of projection exposure objective lens, etc., and whether the image is focused correctly is a basic stone for the normal operation of the system.

Heretofore, methods for achieving focusing of projection images can be classified into active methods and passive methods. The active focusing method can be simply described as calculating the focusing position based on the imaging principle of the system, and judging the position of the CMOS by adopting a distance measuring device. The system firstly carries out accurate calculation on the relation among all distances of the focusing position, then continuously adjusts the relative positions of the workpiece, the CMOS and the lens, and measures the distances through various ranging sensors. The passive focusing method based on machine vision is a focusing process based on the criterion of image definition, after the system collects image data, a computer carries out relevant and effective evaluation calculation on the image, and finally, the operation of a motor is controlled according to the result and a search algorithm, so that the process adjustment of the whole system is realized.

Both of the above-described focusing methods have corresponding disadvantages. Peripheral hardware such as an active focusing frame often has systematic errors, such as manufacturing and installation errors, which can affect the accuracy of ranging. If the measured workpiece has a strong absorption effect on infrared light or ultrasonic waves, the measuring system is out of focus. Ranging does not provide an image sharpness criterion to evaluate whether the focusing result is satisfactory for these drawbacks. Passive focusing relies on complex algorithms and a precise feedback adjustment system, and the system is complex and difficult to get up.

Disclosure of utility model

The utility model provides an automatic focusing device of a high-precision projection exposure machine, which is used for improving focusing precision and simplifying the structure of the device.

In a first aspect, an embodiment of the present utility model provides an automatic focusing device of a high-precision projection exposure machine, including a projection module, a beam splitting module, an electric displacement platform, an image detector and a main control module;

The image detector is positioned on the propagation path of the first image, the target surface to be projected is positioned on the propagation path of the second image, and the distance between the target surface to be projected and the light splitting module is equal to the distance between the image detector and the light splitting module;

The main control module comprises an image acquisition port and a distance control port, wherein the image acquisition port is electrically connected with the image detector and is used for receiving the first image acquired by the image detector, the distance control port is electrically connected with the electric displacement platform, when the definition of the first image does not meet the preset definition requirement, the electric displacement platform is controlled to drive the projection module to move along a first direction until the precision of the first image meets the preset definition requirement, and the first direction is the light emitting direction of the projection module.

Optionally, the focusing projection image is a two-dimensional code image with a resolution of 1920×1080 and a single pixel size of 10 um.

Optionally, the projection module includes a light engine and a lens.

Optionally, the lens is a telecentric lens.

Optionally, the wavelength range of the light source of the optical machine is 510nm-530nm.

Optionally, the main control module further includes a first brightness control port, where the first brightness control port is electrically connected to the optical machine, and adjusts the intensity of the light output by the optical machine when the brightness of the first image does not meet the preset brightness requirement.

Optionally, the main control module further includes a second brightness control port, where the second brightness control port is connected to the image detector, and when the brightness of the first image does not meet the preset brightness requirement, the exposure time of the image detector is controlled.

Optionally, the stroke of the electric displacement platform is 0-30nm.

Optionally, the precision of the electric displacement platform is 1.5um.

Optionally, the light splitting module is a half-mirror, and the half-mirror has a transmittance-reflectance ratio of 50:50;

The image detector is positioned on the light transmission path of the half-mirror, and the target surface to be projected is positioned on the light reflection path of the half-mirror.

The utility model provides an automatic focusing device of a high-precision projection exposure machine, which comprises a projection module, a light splitting module, an electric displacement platform, an image detector and a main control module, wherein the projection module is fixed on the displacement platform, the light splitting module is positioned on a light emergent path of the projection module and divides a focusing projection image emergent from the projection module into a first image and a second image with the same definition, the image detector is positioned on a propagation path of the first image, a target surface to be projected is positioned on a propagation path of the second image, the distance between the target surface to be projected and the light splitting module is equal to the distance between the image detector and the light splitting module, the main control module comprises an image acquisition port and a distance control port, the image acquisition port is electrically connected with the image detector and is used for receiving the first image acquired by the image detector, the distance control port is electrically connected with the electric displacement platform, when the definition of the first image does not meet the preset definition focusing requirement, the electric displacement platform is controlled to drive the projection module to move along a first direction until the accuracy of the first image meets the preset definition requirement, the first direction is the light emergent direction of the projection module, the focal length is adjusted through the projection image, the focal length is adjusted by simplifying the projection image, the accuracy is adjusted, the separation system is adjusted, and the light emergent accuracy is adjusted, and the image separation system is more convenient.

Drawings

FIG. 1 is a schematic diagram of an automatic focusing apparatus for a high-precision projection exposure machine according to an embodiment of the present utility model;

FIG. 2 is a schematic view of an auto-focusing apparatus for a high-precision projection exposure machine according to an embodiment of the present utility model;

fig. 3 is a schematic view of a focusing projection image according to an embodiment of the present utility model.

Detailed Description

The utility model is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present utility model are shown in the drawings.

The terminology used in the embodiments of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. It should be noted that, the terms "upper", "lower", "left", "right", and the like in the embodiments of the present utility model are described in terms of the angles shown in the drawings, and should not be construed as limiting the embodiments of the present utility model. In addition, in the context, it will also be understood that when an element is referred to as being formed "on" or "under" another element, it can be directly formed "on" or "under" the other element or be indirectly formed "on" or "under" the other element through intervening elements. The terms "first," "second," and the like, are used for descriptive purposes only and not for any order, quantity, or importance, but rather are used to distinguish between different components. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The term "comprising" and variants thereof as used herein is intended to be open ended, i.e., including, but not limited to. The term "based on" is based at least in part on. The term "one embodiment" means "at least one embodiment".

It should be noted that the terms "first," "second," and the like herein are merely used for distinguishing between corresponding contents and not for defining a sequential or interdependent relationship.

It should be noted that references to "one", "a plurality" and "a plurality" in this disclosure are intended to be illustrative rather than limiting, and those skilled in the art will appreciate that "one or more" is intended to be construed as "one or more" unless the context clearly indicates otherwise.

Fig. 1 is a schematic diagram of an automatic focusing device of a high-precision projection exposure machine provided by the embodiment of the utility model, fig. 2 is a schematic diagram of a structure of the automatic focusing device of the high-precision projection exposure machine provided by the embodiment of the utility model, referring to fig. 1 and 2, the device comprises a projection module 10, a light splitting module 20, an electric displacement platform 30, an image detector 40 and a main control module 50, wherein the projection module 10 is fixed on the electric displacement platform 30, the light splitting module 20 is positioned on an emergent light path of the projection module 10, a focusing projection image emergent from the projection module 10 is divided into a first image and a second image with the same definition, the image detector 40 is positioned on a propagation path of the first image, a target surface 60 to be projected is positioned on a propagation path of the second image, the distance between the target surface 60 to be projected and the light splitting module 20 is equal to the distance between the image detector 40 and the light splitting module 20, the main control module 50 comprises an image acquisition port 51 and a distance control port 52, the image acquisition port 51 is electrically connected with the image detector 40 and is used for receiving a first image acquired by the image detector 40, the distance control port 52 is electrically connected with the electric displacement platform 30, when the first preset image is not required to be driven by the electric displacement platform 10, and the first image is not required to be driven by the first image to be moved to the first image to be in the preset direction of the definition, and the first image is required to be clear, and the first image is not required to be moved to be clear in the first direction to be the first direction, and the first image is required to be clear, and the image is required to be moved to be the first x clearly is moved.

Specifically, referring to fig. 1 and 2, in order to ensure that the image projected by the projection module 10 onto the target surface 60 to be projected is sufficiently clear, so as to ensure the viewing experience of a user, the beam splitting module 20 is provided, the focusing projection image of the projection module 10 is divided into a first image and a second image with the same definition by using the beam splitting module 20, the second image is projected onto the target surface 60 to be projected, the first image is projected onto the image detector 40, and the distance between the target surface 60 to be projected and the beam splitting module 20 is equal to the distance between the image detector 40 and the beam splitting module 20, so that the first image and the second image formed by the focusing projection image after being split by the beam splitting module 20 are identical in size, and the image information of the first image is acquired from the image detector 40 by using the main control module 50, and the definition of the first image is judged, and when the definition of the first image does not meet the preset definition requirement, namely the image projected onto the target surface 60 also does not meet the preset definition requirement, therefore the distance between the projection module 10 and the target surface 60 is required to be adjusted, and the distance between the projection module and the electric control module is required to be moved to the first image along the preset image 30 by the distance between the target surface 40 and the control platform is required to be moved along the preset image.

The utility model provides an automatic focusing device of a high-precision projection exposure machine, which comprises a projection module, a light splitting module, an electric displacement platform, an image detector and a main control module, wherein the projection module is fixed on the displacement platform, the light splitting module is positioned on a light emergent path of the projection module and divides a focusing projection image emergent from the projection module into a first image and a second image with the same definition, the image detector is positioned on a propagation path of the first image, a target surface to be projected is positioned on a propagation path of the second image, the distance between the target surface to be projected and the light splitting module is equal to the distance between the image detector and the light splitting module, the main control module comprises an image acquisition port and a distance control port, the image acquisition port is electrically connected with the image detector and is used for receiving the first image acquired by the image detector, the distance control port is electrically connected with the electric displacement platform, when the definition of the first image does not meet the preset definition focusing requirement, the electric displacement platform is controlled to drive the projection module to move along a first direction until the accuracy of the first image meets the preset definition requirement, the first direction is the light emergent direction of the projection module, the focal length is adjusted through the projection image, the focal length is adjusted by simplifying the projection image, the accuracy is adjusted, the separation system is adjusted, and the light emergent accuracy is adjusted, and the image separation system is more convenient.

Optionally, fig. 3 is a schematic view of a focusing projection image provided by the embodiment of the present utility model, referring to fig. 3, the focusing projection image is a two-dimensional code image with a resolution of 1920×1080, a single pixel size of 10um, and a high-density four-color-level two-dimensional code is adopted, and after the two-dimensional code image is transmitted to the image detector 40, the accuracy and the efficiency of determining the definition are also higher after the corresponding main control module 50 obtains the two-dimensional code image due to higher resolution of the two-dimensional code image, so that the distance accuracy of controlling the electric displacement platform 30 to drive the projection module 10 to move is also higher.

The projection module 10 includes a light engine and a lens. The lens adopts a telecentric lens, has the advantages of high image resolving power, low distortion rate and the like, and can further improve focusing accuracy. Wherein, the wavelength range of the light source of the optical machine is 510nm-530nm.

Optionally, the main control module 50 further includes a first brightness control port 53, where the first brightness control port 53 is electrically connected to the optical machine, and adjusts the intensity of the light output by the optical machine when the brightness of the first image does not meet the preset brightness requirement.

The preset brightness requirement is understood to be preset according to the image definition recognition capability of the image detector, and may be, for example, a brightness range.

Specifically, when the brightness of the first image does not meet the preset brightness requirement, for example, when the brightness of the image is low, the image detector 40 cannot well identify the definition of the image, and further cannot adjust the focal length according to the definition, so that the brightness of the first image needs to be improved, that is, the intensity of the light output by the optical machine needs to be adjusted.

Optionally, the main control module 50 further includes a second brightness control port 54, where the second brightness control port 54 is connected to the image detector 40, and controls the exposure time of the image detector 40 when the brightness of the first image does not meet the preset brightness requirement.

Specifically, when the brightness of the first image does not meet the preset brightness requirement, the exposure time of the image detector 40 may be adjusted, for example, when the brightness is too high and exceeds the preset brightness requirement, that is, exceeds the preset upper limit of the brightness range, the exposure time of the image detector 40 needs to be reduced, and when the brightness is too low and exceeds the preset lower limit of the brightness range, the exposure time of the image detector 40 needs to be increased.

Optionally, the stroke of the electric displacement platform is 0-30nm. Therefore, the device can realize better focusing effect while ensuring the compactness of the device.

Optionally, the precision of the electric displacement platform is 1.5um, so that when the definition of the electric displacement platform is adjusted by displacement, the higher precision can ensure a better focusing effect.

Optionally, the beam splitting module 20 is a half mirror, the transmission/reflection ratio of the half mirror is 50:50, the image detector 40 is located on the transmission path of the half mirror, and the target surface 60 to be projected is located on the reflection path of the half mirror.

Specifically, in order to ensure that the focusing projection image is divided into a first image and a second image with the same definition by the light splitting module 20, the light splitting module 20 is adopted as a half mirror, and the transmittance ratio of the half mirror is 50:50, that is, the first image divided into the image detector 40 is the same as the second image divided into the target surface 60 to be projected, so that the definition of the second image can be obtained according to the definition of the first image.

Note that the above is only a preferred embodiment of the present utility model and the technical principle applied. It will be understood by those skilled in the art that the present utility model is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements, combinations, and substitutions can be made by those skilled in the art without departing from the scope of the utility model. Therefore, while the utility model has been described in connection with the above embodiments, the utility model is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the utility model, which is set forth in the following claims.

Claims (10)

1. The automatic focusing device of the high-precision projection exposure machine is characterized by comprising a projection module, a light splitting module, an electric displacement platform, an image detector and a main control module;

The image detector is positioned on the propagation path of the first image, the target surface to be projected is positioned on the propagation path of the second image, and the distance between the target surface to be projected and the light splitting module is equal to the distance between the image detector and the light splitting module;

The main control module comprises an image acquisition port and a distance control port, wherein the image acquisition port is electrically connected with the image detector and is used for receiving the first image acquired by the image detector, the distance control port is electrically connected with the electric displacement platform, when the definition of the first image does not meet the preset definition requirement, the electric displacement platform is controlled to drive the projection module to move along a first direction until the precision of the first image meets the preset definition requirement, and the first direction is the light emitting direction of the projection module.

2. The autofocus device of claim 1, wherein the focused projection image is a two-dimensional code image having a resolution of 1920 x 1080 and a single pixel size of 10 um.

3. The autofocus device of claim 1, wherein said projection module comprises a light engine and a lens.

4. An autofocus device according to claim 3, wherein the lens is a telecentric lens.

5. An autofocus device according to claim 3, wherein the light source of the light engine has a wavelength in the range 510nm to 530nm.

6. The autofocus device of claim 3, wherein said main control module further comprises a first brightness control port, said first brightness control port being electrically connected to said light engine, and adjusting the intensity of said light engine output light when the brightness of said first image does not meet a preset brightness requirement.

7. The autofocus apparatus of claim 1, wherein said main control module further comprises a second brightness control port, said second brightness control port being coupled to said image detector for controlling an exposure time of said image detector when a brightness of said first image does not meet a preset brightness requirement.

8. The autofocus device of claim 1, wherein the motorized displacement platform has a travel of 0-30nm.

9. The autofocus device of claim 1, wherein the precision of the motorized displacement platform is 1.5um.

10. The autofocus apparatus of claim 1, wherein the beam splitting module is a half mirror, and the half mirror has a transmittance to reflectance ratio of 50:50;

The image detector is positioned on the light transmission path of the half-mirror, and the target surface to be projected is positioned on the light reflection path of the half-mirror.