Stray light eliminating structure of lens

Abstract

The utility model discloses a lens stray light eliminating structure comprising a lens housing, the lens housing is provided with an entrance port, an exit port and a reflection port, a reflection assembly is arranged in the lens housing, a DMD chip is arranged at a position, corresponding to the reflection port, of the outer side of the lens housing, the DMD chip and the reflection assembly correspondingly form a reflection light path, a stray light eliminating cavity is arranged in the lens housing, and the DMD chip and the reflection assembly form a reflection light path. An inlet of the stray light elimination cavity corresponds to a stray light directional reflection path of the DMD chip, stray light can form a fixed reflection path in the lens, and the DMD chip can reflect the stray light no matter the lens stops working or is in a working state, so that the stray light elimination cavity is arranged in the lens shell, and the DMD chip can reflect the stray light. Unneeded stray light is directly reflected into the stray light eliminating cavity, the stray light is absorbed and eliminated to achieve the stray light emitting effect, the other part of light is reflected to the exit port through the DMD chip and forms an image after passing through the lens, and therefore the stray light is eliminated, and the imaging contrast ratio and the imaging quality of the lens are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of lens imaging, and specifically relates to a lens stray light elimination structure. Background Art

[0002] In a laser direct writing lithography system, the most core part is the DMD chip. When the DMD chip is in the on state, the imaging light passes through the lens and forms an image. However, when the DMD chip is in the off state, it will generate directional reflected light, and the reflected light will enter the lens and become unwanted stray light, which is an unavoidable phenomenon. The current solution is to blacken the inner wall surface of the lens to eliminate stray light. However, through long-term use, it is found that this solution can only eliminate a very weak part of the light, while the reflected light of the DMD chip is very strong. With the passage of time and the irradiation of light, the blackened layer on the inner wall of the lens will turn white, eventually forming reflection, generating a large amount of stray light and entering the effective area of the lens, reducing the lens contrast. With the irradiation of light, the lens will generate a relatively high temperature. As the heat accumulates, the size of the lens will deform, reducing the lens imaging quality. Content of the Utility Model

[0003] The purpose of the utility model is to provide a lens stray light elimination structure to solve the problems raised in the above background art.

[0004] To achieve the above purpose, the utility model provides the following technical solutions:

[0005] A lens stray light elimination structure includes a lens housing, the lens housing is provided with an incident port, an exit port, a reflection port, and a reflection component is arranged inside it. A DMD chip is arranged outside the lens housing corresponding to the reflection port, and the DMD chip and the reflection component form a reflection optical path. A stray light elimination cavity is arranged inside the lens housing, and the entrance of the stray light elimination cavity corresponds to the stray light directional reflection path of the DMD chip.

[0006] Further, a light extinction pattern is arranged at the bottom of the stray light elimination cavity.

[0007] Further, the light extinction pattern is perpendicular to the incident light direction.

[0008] Further, a black coating is arranged on the inner wall of the stray light elimination cavity.

[0009] Further, the reflection component includes a first mirror and a second mirror, a first lens is arranged at the incident port, and a second lens is arranged between the first mirror and the second mirror.

[0010] Further, the first lens is a plano-convex lens, and the second lens is a convex lens.

[0011] Further, it further includes a heat dissipation structure for dissipating heat from the lens housing.

[0012] Further, the heat dissipation structure includes a circulating water path formed to communicate with the inside of the lens housing. The water path forms a water inlet and a water outlet on the surface of the lens housing for connection to an external water cooling device.

[0013] Advantages of the present utility model:

[0014] Stray light will form a fixed reflection path in the lens. Whether the lens is stopped or in operation, the DMD chip will reflect the stray light. Therefore, in the present utility model, a stray light elimination cavity is provided inside the lens housing to directly reflect the unwanted stray light into the stray light elimination cavity, absorb and eliminate the stray light, so as to achieve the effect of removing stray light. Another part of the light is reflected by the DMD chip to the exit port and imaged through the lens, thereby achieving the purpose of eliminating stray light, improving the contrast of the lens imaging and the imaging quality.

[0015] The present utility model is provided with a circulating water path communicating with the inside of the lens housing. The water path forms a water inlet and a water outlet on the surface of the lens housing for connection to an external water cooling device. The water path flows through the DMD chip and the stray light elimination cavity, absorbs the surface heat thereof, and improves the heat dissipation effect of the lens housing.

[0016] Other features and advantages of the present utility model will be described in detail in the subsequent specific implementation section. Description of the Drawings

[0017] Figure 1 : Overall structure diagram of the present utility model.

[0018] Figure 2 : Cross-sectional internal structure of the present utility model Figure 1 。

[0019] Figure 3 : Cross-sectional internal structure of the present utility model Figure 2 。

[0020] Figure 4 : Cross-sectional plan view of the present utility model.

[0021] Figure 5 : Optical path diagram of the working state of the DMD chip of the present utility model.

[0022] Figure 6 : Optical path diagram of the off state of the DMD chip of the present utility model.

[0023] Reference numerals: 1, lens housing; 2, incident port; 3, reflection assembly; 4, DMD chip; 5, stray light elimination cavity; 6, exit port; 7, water inlet; 8, water outlet; 9, reflection port; 31, first mirror; 32, second mirror; 33, first lens; 34, second lens; 51, extinction pattern. Detailed implementation manners

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0025] Please refer to Figures 1-6 ;

[0026] A lens stray light elimination structure includes a lens housing 1. The lens housing 1 is a carrier for carrying optical devices and optical paths. The lens housing 1 is provided with an incident port 2, an exit port 6, a reflection port 9, and a reflection assembly 3 is provided inside it. A DMD chip 4 is provided outside the lens housing 1 at a position corresponding to the reflection port 9. The DMD chip 4 and the reflection assembly 3 form a reflection optical path. Light enters the inside of the lens housing 1 from the incident port 2, and the light is reflected to the DMD chip 4 through the reflection assembly 3. The DMD chip 4 processes the light source to generate imaging light, and the imaging light exits from the exit port 6 and forms an image after passing through the lens. Since stray light enters when the DMD chip 4 is in the off state, the DMD chip 4 will reflect this stray light. The light in the off state includes the light originally staying inside the lens housing 1 and the light entering from the external lens or the lens gap. This light will be reflected by other structures inside the lens, and these stray lights will form a fixed reflection path. When the lens is in use, these stray lights will affect the imaging quality of the DMD chip 4. Therefore, a stray light elimination cavity 5 is provided inside the lens housing 1. The entrance of the stray light elimination cavity 5 corresponds to the stray light directional reflection path of the DMD chip 4. The DMD chip 4 injects the stray light into the stray light elimination cavity 5, and the stray light elimination cavity 5 absorbs and eliminates these stray light rays, thereby achieving the effect of eliminating stray light, enabling the required imaging light to exit from the exit port 6, and improving the contrast of the lens imaging and the purpose of the imaging quality.

[0027] Specifically, light enters from the incident port 2. The incident light is reflected by the reflection component 3 onto the DMD chip 4. Some unwanted stray light is reflected by the DMD chip 4 into the stray light elimination cavity 5, where the stray light is absorbed and eliminated. The other part of the light is reflected by the DMD chip 4 to the exit port 6 and forms an image after passing through the lens. When the lens is not in use, the DMD chip 4 is set to the off state, and the DMD chip 4 directly reflects the unwanted stray light into the stray light elimination cavity 5 without reflecting the stray light out. When the lens is in use, the DMD chip 4 is in the ON state. The DMD chip 4 reflects the stray light into the stray light elimination cavity 5 and emits the required imaging light from the exit port 6. The imaging light forms an image after passing through the lens.

[0028] In this embodiment, extinction stripes 51 are provided at the bottom of the stray light elimination cavity 5. The extinction stripes 51 are perpendicular to the direction of the incident light. The extinction stripes 51 can scatter the stray light reflected in the stray light elimination cavity 5 to achieve extinction. The reflection direction of the stray light always faces the enclosed area and will not be reflected back to the lens, so that the stray light will not be projected together with the light imaging on the DMD chip 4, improving the contrast of the lens imaging.

[0029] Furthermore, a black coating is provided on the inner wall of the stray light elimination cavity 5. The black coating can strongly absorb the light effect to eliminate the stray light or reduce the light effect scattering.

[0030] In this embodiment, the reflection component 3 includes a first mirror 31 and a second mirror 32. A first lens 33 is provided at the incident port 2. Preferably, the first lens 33 is a plano-convex lens with its convex surface facing the first mirror 31, which is used to focus the incident light into parallel light. A second lens 34 is provided between the first mirror 31 and the second mirror 32. Preferably, the second lens 34 is a convex lens, which is used to converge the parallel light reflected by the first mirror 31. The first mirror 31 and the second mirror 32 are respectively arranged at a set angle. The first mirror 31 reflects the light to the second mirror 32, and the second mirror 32 then reflects the light to the DMD chip 4, and then the DMD chip 4 forms an image of the light and reflects it out.

[0031] Since the components that the lens needs to reflect light will generate heat when irradiated by light, which causes the temperature of the lens to rise. As the temperature of the lens rises, it will lead to deformation of the lens size, affecting the imaging quality. Therefore, a lens stray light elimination structure further includes a heat dissipation structure. The heat dissipation structure is used to dissipate heat from the lens housing 1. The heat dissipation structure can be air-cooled heat dissipation. For example, a fan is set outside. Because the stray light elimination cavity 5 needs to absorb stray light, it is inevitable that a large amount of heat will accumulate inside the stray light elimination cavity 5. Therefore, a fan is set on the corresponding path between the stray light elimination cavity 5 and the DMD chip 4 to directly dissipate heat from the DMD chip 4 and the stray light elimination cavity 5. Heat dissipation fins can also be set on the outer periphery of the lens housing 1 to absorb the heat of the lens housing 1. When the fan blows air on the lens housing 1, the heat of the heat dissipation fins can be quickly dissipated, thereby improving the heat dissipation effect of the lens housing 1. And the present utility model preferably adopts water-cooled heat dissipation. The water-cooled heat dissipation specifically includes a circulating water path communicating with the inside of the lens housing 1. The water path forms a water inlet 7 and a water outlet 8 on the surface of the lens housing 1 for connecting with an external water-cooling device. The water path flows through the DMD chip 4 and the stray light elimination cavity 5 to absorb the heat on their surfaces and improve the heat dissipation effect of the lens housing 1.

[0032] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and without departing from the spirit or basic characteristics of the present utility model, the present utility model can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present utility model. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0033] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other implementations that those skilled in the art can understand.

Claims

1. A lens stray light elimination structure, comprising a lens housing (1), the lens housing (1) is provided with an incident port (2), an exit port (6), a reflection port (9), and a reflection component (3) is arranged inside it. A DMD chip (4) is arranged outside the lens housing (1) at a position corresponding to the reflection port (9). The DMD chip (4) and the reflection component (3) correspond to form a reflection optical path, characterized in that, A stray light elimination cavity (5) is provided inside the lens housing (1), and the entrance of the stray light elimination cavity (5) corresponds to the stray light directional reflection path of the DMD chip (4).

2. The stray light elimination structure of a lens according to claim 1, wherein, A light extinction pattern (51) is provided at the bottom of the stray light elimination cavity (5).

3. The stray light elimination structure of a lens according to claim 2, characterized in that, The light extinction pattern (51) is perpendicular to the incident light direction.

4. A stray light elimination structure for a lens according to claim 2, characterized in that The inner wall of the stray light elimination cavity (5) is provided with a black coating.

5. A stray light elimination structure for a lens according to claim 1, characterized in that, The reflection assembly (3) includes a first mirror (31) and a second mirror (32), a first lens (33) is provided at the incident port (2), and a second lens (34) is provided between the first mirror (31) and the second mirror (32).

6. The stray light elimination structure of a lens according to claim 5, wherein, The first lens (33) is a plano-convex lens, and the second lens (34) is a convex lens.

7. A stray light elimination structure for a lens according to claim 1, wherein, It further includes a heat dissipation structure for dissipating heat from the lens housing (1).

8. A stray light elimination structure for a lens according to claim 7, characterized in that The heat dissipation structure includes a circulating water path formed to communicate with the inside of the lens housing (1), and the water path forms a water inlet (7) and a water outlet (8) on the surface of the lens housing (1) for connecting to an external water cooling device.

Images