CN111505892A

CN111505892A - Projection system based on micro-lens array

Info

Publication number: CN111505892A
Application number: CN201910090082.6A
Authority: CN
Inventors: 王杰芳
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-01-30
Filing date: 2019-01-30
Publication date: 2020-08-07

Abstract

A projection system based on a micro-lens array is composed of a light source (1), an illumination collimation assembly (2) and a micro-lens projection assembly (3), wherein the illumination collimation assembly is not limited to L ED and is mainly used for collimating light emitted by the light source to form an illumination light beam close to parallel light and used for illuminating a rear micro-lens projection assembly, and the micro-lens projection assembly is mainly used for projecting and imaging patterns.

Description

Projection system based on micro-lens array

Technical Field

The invention relates to the field of projection lamps and greeting lamps, in particular to an automobile projection lamp and an automobile greeting lamp.

Background

The welcome lamp on the automobile is welcomed by a honoured guest, and has a particularly obvious effect in dark days or at night, wherein the welcome lamp comprises an L ED lamp, a film module with a pattern and an imaging module for projecting the pattern on a bottom surface or a wall body, and the operating principle is that light rays emitted by the L ED lamp pass through the film module and project the shape of the pattern in a light shape from the imaging module to form a light pattern on the bottom surface.

Disclosure of Invention

The projection system based on the micro-lens array mainly solves the problem of high-definition and high-precision projection imaging under the condition of oblique illumination.

The projection system comprises a light source (1), an illumination collimation assembly (2) and a micro-lens projection assembly (3), wherein the micro-lens projection assembly is mainly used for projecting a pattern, the light source of the system adopts L ED, a laser and the like as an illumination light source, the illumination collimation assembly of the system can be a reflection type optical system, a transmission type optical system or a diffraction optical system, the illumination collimation assembly has the functions of collimating and homogenizing divergent light emitted by the light source to form an illumination light beam close to parallel light and illuminating a rear end micro-lens projection assembly, the light emitted by a light source L ED light source is reflected to form a collimated illumination light beam after being irradiated on the reflection type optical system, and further provides illumination light for the micro-lens projection assembly, the most classical reflection structure is a L ED light reflecting cup, a L ED light source is positioned at the focal position of the L ED light source, the light emitted by a light source of the 392 ED light source is reflected by the reflecting cup to form a parallel collimated light beam, and the illumination light beam is emitted by a Fresnel refraction type micro-lens projection assembly, the projection system also can adopt a single-piece or a plurality of light sources formed by an ED 5, and a Fresnel refraction type projection lens set which emits a collimated light source, and a Fresnel refraction type projection lens, and a Fresnel lens assembly is formed by folding type projection lens 38964.

The microlens projection assembly in the microlens array projection system proposed by the patent is composed of a microlens array 31, a microimage 32 and a microlens array 33 in sequence. The micro lens array 31 and the micro lens array 33 are both plano-convex micro lens arrays, the arrangement modes of the micro lens array 31 and the micro lens array 33 are completely the same, and the micro lens units of the micro lens array 31 and the micro lens units of the micro lens array 33 are in mutual centering and are in one-to-one correspondence;

after the light beam emitted from the illumination collimation assembly passes through the micro lens array 31, the light beam emitted from each micro lens unit in the micro lens array 31 must be capable of completely irradiating the pattern in the corresponding unit of the micro image-text 32 which is close to the rear of the micro lens array and corresponds to the micro lens unit; the sub-aperture of the micro-lens array 31 and the sub-aperture of the micro-lens array 33 may be equal or unequal, but the light beam emitted from each unit of the micro-image 32 must be able to fully irradiate the corresponding micro-lens unit in the micro-lens array 33;

the micro-lens array 31 and the micro-image 32 in the micro-lens projection assembly are tightly attached, and each unit of the micro-image 32 is placed at the center position of the corresponding unit of the micro-lens array 31 as far as possible, the micro-image 32 is positioned at the object focal plane of the micro-lens array 33, the focal length f31 of the micro-lens array 31 and the focal length f33 of the micro-lens array 33 meet the following relation that f31 is more than or equal to (f33 ＊ 1/2), f31 is optimally selected to be f33, and when f31 is infinite, the micro-lens array 31 evolves to a plane;

the microimage 32 in the microlens projection assembly is obtained by: placing a light-emitting source which is the same as the target pattern according to parameters such as a projection angle, a projection distance and the like; then, placing the micro-lens array 33 at a corresponding position according to the application scene requirements, imaging the light-emitting source by adopting the micro-lens array 33, placing a photoetching offset plate at the focal plane of the image space of the micro-lens array 33, and collecting the image formed by each micro-lens in the micro-lens array; because the imaging area of the photoresist is sensitized, the photoresist in the imaging area is removed after development, and because other areas are not irradiated by imaging light, the photoresist is not sensitized and cannot be removed; finally, the required micro-graph and text can be obtained on the photoetching offset plate. Finally, the micro-image and text 32 composed of the light passing and light blocking areas is obtained through the traditional processes of film coating, cleaning, photoetching copying and the like; the micro-graph and text can be carried on the surface of a sheet material made of various materials such as a glass sheet, a film, a quartz plate, a plastic sheet and the like;

the micro-lens projection assembly included in the micro-lens projection system described in this patent may be formed by bonding three parts, namely, a micro-lens array 31, a micro-image 32, and a micro-lens array 33, into a whole; the micro-lens array 31 and the micro-lens array 33 can be arranged separately according to a required position relationship, the surface of the micro-lens array 31 and the micro-lens array 33 can be spherical, or quadric or other aspheric surfaces, the arrangement mode of the micro-lens array 31 and the micro-lens array 33 can be quadrilateral arrangement, hexagonal arrangement and the like, and the front surface and the back surface of the micro-image 32 can be subjected to anti-reflection treatment including but not limited to black dyeing, black chromium plating and the like;

compared with the prior art, the invention has the beneficial effects that:

the prior projection technology can only form clear projection effect under the condition of vertical illumination or nearly vertical illumination. For large angle oblique illumination, it is difficult to obtain high definition illumination. The present invention addresses this problem.

In addition, the collimated light beam is adopted to illuminate the micro-lens projection system, so that the definition of the micro-lens projection system and the utilization rate of light energy can be greatly improved.

Drawings

FIG. 1 is a schematic diagram of a microlens array-based projection system according to the present invention; 1 is a light source, 2 is an illumination collimation assembly, 3 is a micro-lens projection assembly, 31 is a front micro-lens array in the micro-lens projection assembly, 32 is a micro-image and text in the micro-lens projection assembly, and 33 is a rear micro-lens array in the micro-lens projection assembly

FIG. 2 is a partial magnified optical path view of a microlens projection assembly;

FIG. 3 illustrates an application scenario and an application manner of a microlens array projection system according to an embodiment

Figure 4 illustrates an embodiment of a microlens array projection system,

in the embodiment of FIG. 5, the micro-pattern 321 obtains the light path and the light-emitting pattern 51 which is the same as the expected pattern on the light path

In the first embodiment of FIG. 6, the micro-image 321 obtains the image of the micro-lens in the optical path

FIG. 7 is a diagram of the micrograph 321 obtained in the first embodiment

FIG. 8 shows a projection imaging optical path of a microlens projection assembly according to an embodiment

Figure 9 is a front view of the projection system with microlens array in embodiment 2 and microlens array 312 and microlens array 332,

figure 10 micrographs 3221 obtained in embodiment 2

FIG. 11, micro-pattern 322 after cutting in example 2

FIG. 12 projection imaging optical path of microlens projection assembly in embodiment 2

FIG. 13, projection system of microlens array as shown in embodiment 3

FIG. 14 is a light path diagram of a projection module of a microlens in a microlens array projection system as shown in example 3

FIG. 15 application of the microlens array projection system of embodiment 4

FIG. 16 microlens array projection System of embodiment 4

FIG. 17 optical path diagram of microlens projection assembly of embodiment 4

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. As shown in fig. 1, the present invention provides a projection system based on a microlens array, comprising: the device comprises a light source (1), an illumination collimation assembly (2) and a micro-lens projection assembly (3); the three parts are sequentially arranged, divergent light emitted by the light source forms collimated light beams after passing through the illumination collimation assembly, and after the collimated light beams illuminate the micro-lens projection assembly, superposed, clear and optical projection meeting application requirements is formed at a distance;

the projection light source can be L ED light source, the illumination collimation assembly can be formed by reflection optical system such as reflection cup, secondary reflection curved surface, etc., or by refraction lens or refraction lens group, furthermore, for compressing volume, it can also be formed by diffraction optical device and system such as Fresnel lens, etc., the micro lens projection assembly at least comprises two optical channels, the micro lens unit of the micro lens array 31 and the corresponding unit in the micro image 32 and the corresponding micro lens unit in the micro lens array 33 form an optical channel, the pattern projected by each optical channel forms a clear and single pattern after being superposed at far distance, the micro lens array 31 unit, the micro image 32 unit and the micro lens array 33 unit mutually correspond to each other in center, the micro lens array 31 unit focuses parallel light to the position near the curved surface vertex of the micro lens array 33 unit, the micro image 32 is positioned on the front focal surface of the micro lens array 33, the micro lens array 33 unit projects the corresponding micro image 32 unit to the object point in detail, the micro lens projection assembly partially magnifies the light path, see FIG. 2, the head surface of FIG. 2 shows, the light represents the position of the light of the micro lens array, and the micro lens array 33 represents the position of the detailed description of the micro lens array, and the arrow of the micro lens array 33.

Embodiment 1 is a microlens array projection system applied to a chassis position behind a front wheel of a vehicle, the height requirement L1 of the microlens array projection system 101 is 200mm from the ground 102, and a microlens projection assembly is placed with the ground at an angle of Q1 (the central normal of the microlens projection assembly forms an angle of 90-60 degrees to 30 degrees with the ground), pattern projection is performed, a target projection area 41 and a projected pattern 42 are as shown in fig. 3, the overall use environment and parameters are as shown in fig. 3, the light source used by the microlens array projection system (as shown in the left side of fig. 4) is L ED11, the illumination collimation assembly is composed of a reflector cup 21, the microlens projection assembly is composed of two groups of microlens arrays with completely identical structural parameters, the

microlens arrays

311 and 331 are both arranged in a hexagonal manner, the microlens sub-apertures are both 0.8mm, the central distances of the microlenses are both 0.8mm, the focal lengths of the microlens arrays 311 are f311, the focal lengths of the microlens arrays 331 are both f331, f is 331 is 2.331, the microlens arrays 331 are both located on the right side of the microlens arrays, and the light rays of the microlens arrays are located on the curved surface of a parabolic curved surface of a microlens 311, and a microlens 321, and a microlens array 331 are located on the right side of the off-axis, and a curved surface of a parabolic surface of a microlens 311, and a microlens array 331, and a microlens 311, and a.

The micro-pattern 321 is obtained by a method that an obtaining system sets a light-emitting pattern 51 which is the same as an expected pattern in a ground target projection area 41 according to application scene requirements as shown in FIG. 5, the light-emitting pattern can be formed by L ED illuminating frosted glass, other non-light-emitting areas are blackened, shaded and absorbed, an insert in the upper right corner in FIG. 5 is that the ground target projection area 41 and the light-emitting pattern 51 contained in the period are white to represent a light-emitting area, other surrounding black areas and peripheral areas are non-light-transmitting areas, a micro-lens array 34 with the aperture of 0.8mm, the center distance of 0.8mm and the focal length of 2.8mm which is completely the same as the parameters of a micro-lens array 331 is placed at the height of 200mm from the ground in a use state, and the micro-lens array 34 and the ground form a position of 60 degrees with the angle, and a central light extension 61 of the micro-lens array 34 is coincident with the center of the light-emitting pattern 51, and finally a photoresist plate 35 is placed at a focal plane behind the micro-lens array 34, the light-sensitive mask 35 is imaged, the light-sensitive mask is formed by a micro-image-forming system, if a large number of micro-sensitive photo-mask, a micro-mask is needed micro-mask pattern is formed by a micro-mask, a micro-mask pattern forming mask, a micro-mask pattern is formed by a micro-mask, a micro-mask pattern forming system, a micro-mask pattern forming system is used, a micro-mask, a mask is used mask, a mask is used for forming process, a mask is used for forming micro-mask, a mask is used mask, a;

placing the microimage 321 close to the microlens array 311 in parallel, and simultaneously placing the microimage 321 and the microlens array 331 in parallel with the distance equal to the focal length f 331; the

microlens arrays

311 and 331 are ensured to be in one-to-one centering correspondence, and the central optical axes of the corresponding microlens units are coincident, as shown in fig. 8.

The projection principle of the microlens array projection system of this embodiment 1 is shown in fig. 4, light emitted from a single chip L ED11 enters the reflective cup 21, after reflection, the light is converted from divergent light to collimated light (the intensity of cross section of the collimated light is uniformly distributed), the light illuminates the microlens array 311, each microlens unit of the microlens array 311 converges the incident light, illuminates the corresponding area of the microimage 321, and after imaging through the microlens array 331, the incident light is fused into a unique and clear projection pattern shown in the upper right corner of fig. 5 on the far ground, as shown in fig. 4 and fig. 8.

Example 2: in response to the same application requirements as those of embodiment 1, the present invention provides another uniform imaging microlens array projection system applied to the chassis position behind the front wheels of the vehicle. The height requirement of the microlens array projection system 101 and the ground 102 is 200mm, and the microlens projection assembly projects a pattern at an angle of 60 degrees with respect to the ground, and the target projection area 41 and the projected pattern 42, the overall use environment and parameters are as shown in fig. 2.

In order to achieve the above effect, this embodiment provides another solution as shown in fig. 9, in which the light source used by the microlens array projection system is L ED12, the illumination collimation assembly is composed of 2 transmissive optical lens assemblies 22, each of the microlens array 312 and the microlens array 332 adopts a hexagonal arrangement, the sub-aperture of the microlens array 312 is 0.8mm, the sub-aperture of the microlens array 332 is 0.4mm, the period of the microlenses (i.e. the distance between the centers of the microlenses and the microlenses) in the microlens array 312 and the microlens array 332 is 0.8mm, the arrangement is shown in the right drawing of fig. 9, and there are 18 total microlenses, the focal length of the microlens array 312 is f312, the focal length of the microlens array 332 is f332, f312 is 2.8mm, the microlens array 312 and the microlens array 332 are located at the focal plane of the microlens array 332, the surface shapes of the microlens array 312 and the microlens array 332 can be an off-axis quadric surface, a B surface, preferably 1 is a paraboloid microlens array 312, and the image-text-image area of each microlens 322 completely covers the light-transmitted microlens 322 from the microlens array 322;

in this embodiment, the microimage 322 can be obtained by the method for obtaining the microimage 321 as in the first embodiment, and two aspects of adaptive adjustment need to be performed in the process of obtaining the microimage 322: 1. the microlens array 34 in fig. 3 is replaced by the microlens array 342 with the same parameters as the microlens array 332 in the first embodiment: the parameters are as follows, the sub-aperture is 0.4mm, the center distance is 0.8mm, the focal length is 2.8mm, and in addition, the non-microlens area in the microlens array 342 needs to be processed with light resistance treatment such as black dyeing; 2. in the same process as the process for obtaining the microimages 321 in embodiment 1, after the microlens array 342 is placed at the corresponding position for exposure and development, a microimage 3221 is obtained on the photoresist plate, as shown in fig. 10; because the ground areas covered by different angles in the projection process of the projection system are different, namely: under the condition that the section intensity of the light beam emitted by the illumination collimation assembly is uniform, light obliquely projected to a far place (such as the tail part of a vehicle) covers a larger area, the brightness is dark, light projected to a near place (such as the front door of the vehicle) covers a relatively small area, the brightness is brighter, and in order to reduce the front-back brightness contrast of the vehicle body, the projection brightness of the front part of the vehicle body can be reduced; the specific operation is as follows: each group of the obtained micro-images and texts 3221 is respectively processed, and micro-image and text light-transmitting areas in different brightness areas are covered in proportion according to the requirement of illumination brightness; in this embodiment, each of the microlens arrays 332 and 342 has 18 microlens elements, so the post-lithography microlithographic features 3221 also consist of 18 sets of microlithographic features; we remove the area of group 15 of fronts 1/6, group 12 of fronts 2/6, group 9 of fronts 3/6, group 6 of fronts 4/6, and group 3 of fronts 5/6, and finally form the micrograph 322 we want, as shown in fig. 11. The illumination effect with consistent projection intensity can be relatively realized by performing projection imaging by using the microimage-text 322, and in fig. 11, a circular dotted line represents an area mapped correspondingly to the microlenses 342 and 332; the rectangle dotted line frame represents a transparent area cut off by a load, and the area is changed from transparent to opaque; the optical path of the microlens projection assembly in this embodiment is shown in fig. 12.

The cutting ratio and effect of the micrograph 322 in this embodiment are shown as examples, and other cutting ratios and cutting strategies are within the scope of the present disclosure.

Embodiment 3. a microlens array projection system applied to a chassis position behind a front wheel of a vehicle according to the present invention, the height requirement of the microlens array projection system 101 and the ground 102 is 200mm, and a microlens projection assembly projects a pattern at an angle of 60 ° with respect to the ground, a target projection area 41 and a projected pattern 42 are as shown in fig. 2, a light source used by the microlens array projection system is L ED13, an illumination collimation assembly is composed of fresnel lens groups 23, a microlens projection assembly is composed of two groups of microlens arrays and microimages, the microlens arrays 313 and the microlens arrays 333 are arranged in a hexagonal manner, the aperture of each microlens is 0.8mm, the center distance of each microlens is 0.8mm, the focal length of the microlens arrays 313 is f313, the focal length of the microlens arrays 333 is f333, f313 is 5.6mm, f333 is 2.8mm, the microimages are located at the focal plane of the microlens arrays 333, the microlens arrays 313, the focal length of the microlens arrays 313 is completely 333, the image of the images are obtained by a microlens arrays 323, a microlens array 323, a single-based on the principle that a light path of a microlens array 13, a microlens array is formed by a microlens array, a microlens array 23, a microlens array is formed by a single-based on a rear projection system, a microlens array, a rear projection system, a rear projection light path is formed by a microlens array, a microlens array is formed by a microlens array, a microlens array is a microlens array, a microlens array is a microlens array, a microlens array is formed by a microlens array, a rear projection system is a microlens array, a rear projection system is formed by a microlens array, a microlens array is a microlens array, a rear projection system is.

Embodiment 4. a microlens array projection system for a vehicle rearview mirror position according to the present invention, in which only one microlens array is required to achieve projection imaging, the height requirement of the microlens array projection system 401 and the ground 402 is L-1200 mm, and the microlens projection assembly projects a pattern at an angle of Q4-30 ° with respect to the ground, a target projection area 441 and a projected pattern 442 are shown in fig. 15. the light source used in the microlens array projection system is L ED14, the illumination collimation assembly is composed of a single refraction and reflection PMMA lens group 24, the microlens projection assembly is composed of a microlens array 334 and a microlens 324 (the focal length of the microlens array 314 at the front end of the microlens 324 is infinitely large, so the microlens array 314 evolves into a transparent plane, which coincides with the microlens array 324), the microlens array 334 is arranged in a quadrilateral manner, the microlens sub-aperture is 0.8mm, the center distance of the microlenses is 0.8mm, the microlens array has a focal length f 2, which is coincident with the center of the microlens array 324, the collimating light ray of the microlens array 324 is emitted from the microlens array 334, the microlens array 324, the collimating light ray path of the microlens array 324, the collimating light ray is reflected from the microlens array 324, the collimating light ray is reflected from the microlens array 324, the collimating light ray of the microlens array 324, the collimating light ray is formed into a single-collimating light ray, the collimating light ray path of the collimating light ray, the collimating light ray of the collimating lens array 324, the collimating light ray of the collimating lens array 324, the collimating lens.

Claims

1. A projection system based on a micro-lens array is characterized by sequentially comprising a light source (1), an illumination collimation assembly (2) and a micro-lens projection assembly (3).

2. A projection system based on micro-lens array as claimed in claim 1, wherein the light source of the system is L ED.

3. A microlens array based projection system as claimed in claim 1, wherein: the illumination collimation component of the system can be a reflection type optical system, and also can be a transmission type optical system or a diffraction optical system; the function of the collimating lens is to collimate diverging light emitted by the light source to form an illumination beam close to parallel light to illuminate the rear end micro-lens projection assembly.

4. The reflective optical system of claim 3, wherein the light from the light source L ED is reflected to form a collimated illumination beam, which is then used to provide illumination light to the micro-lens projection module.

5. A transmissive optical system as claimed in claim 3 comprising an illumination collimating assembly, wherein the transmissive optical system comprises a single lens or a plurality of lenses, and wherein light from the L ED light source is refracted by the lens assembly and collimated into a parallel beam to exit and illuminate the microlens projection assembly.

6. The diffractive optical system of claim 3, wherein the diffractive optical system comprises 1-2 Fresnel lenses or folded catadioptric lenses, and L ED light source emits parallel collimated light beams after passing through the diffractive optical system and illuminates the micro-lens projection module.

7. A microlens array based projection system as claimed in claim 1, wherein: the micro-lens projection component of the system consists of a micro-lens array 31, a micro-image 32 and a micro-lens array 33 in sequence. The micro lens array 31 and the micro lens array 33 are both plano-convex micro lens arrays, the arrangement modes of the micro lens array 31 and the micro lens array 33 are completely the same, and the micro lens units of the micro lens array 31 and the micro lens units of the micro lens array 33 are in mutual centering and are in one-to-one correspondence; each microlens unit in the microlens array 31 and each microlens unit in the microlens array 33 form a multi-path optical channel in a one-to-one correspondence mode, and each group of patterns in the micro image text 32 are illuminated and imaged respectively; some of the groups of patterns of the microimages 32 can be projected into a complete target projection pattern, and some of the groups of patterns can be projected into a partial target projection pattern, but the patterns formed after the groups of patterns of all the microimages 32 are projected are overlapped at a distance; after the light beam emitted from the illumination collimation assembly passes through the micro lens array 31, the light beam emitted from each micro lens unit in the micro lens array 31 must be capable of completely irradiating the pattern in the corresponding unit of the micro image-text 32 which is close to the rear of the micro lens array and corresponds to the micro lens unit; the sub-aperture of the micro-lens array 31 and the sub-aperture of the micro-lens array 33 may be equal or unequal, but the light beam emitted from each unit of the micro-image 32 must be able to be projected into the corresponding micro-lens unit in the micro-lens array 33, and no energy can be irradiated to the ineffective area between the micro-lens units, and the area of the micro-lens array 31 not filled by the micro-lens units can be preferably subjected to light blocking treatment such as but not limited to black dyeing, shading, metal coating and the like; the areas of the microlens array 33 not filled with the microlens units may be preferably subjected to, but not limited to, light blocking treatment such as black dyeing, light blocking, metal plating, and the like.

8. The micro-lens projection assembly of claim 1, wherein the micro-lens array 31 is closely attached to the micro-graphics 32, and each unit of the micro-graphics 32 (i.e. each group of micro-graphics 32 included in the micro-graphics) is placed at the center of the corresponding unit of the micro-lens array 31 as much as possible to ensure that each group of micro-graphics 32 can be completely irradiated by the light beam emitted from the corresponding micro-lens unit of the micro-lens array 31, the micro-graphics 32 is located at the object focal plane of the micro-lens array 33, all the micro-lenses in the micro-lens array 31 have the same focal length f31, all the micro-lenses in the micro-lens array 33 have the same focal length f33, and f31 and f33 satisfy the following relationship that f31 is ≧ (f33 ＊ 1/2), and f31 is optimally selected as f33, and when f31 is infinite, the micro-lens array 31 evolves to a plane.

9. The micrographs 32 of claim 8, wherein: the microimage 32 in the microlens projection assembly is obtained by: setting a light-emitting source which is the same as the target projection pattern according to application scene parameters such as projection angle, projection distance and the like, then placing the micro lens array 33 at a corresponding position according to application scene requirements, and imaging and photoetching the light-emitting source by adopting the micro lens array 33; the specific operation is as follows: placing a photoetching offset plate on the focal plane of the image space of the micro-lens array 33, and collecting the image formed by each micro-lens in the micro-lens array; because the imaging area of the light source in the photoresist plate is sensitized, the photoresist in the imaging area is removed after development, other areas are not irradiated by imaging light, and the photoresist is not sensitized and cannot be removed; thus obtaining the micro-graph and text of the photoresist material on the photoresist offset plate. Finally, the micro-image and text 32 composed of the light passing and light blocking areas is obtained through the traditional processes of film coating, cleaning, photoetching copying and the like; the micro-graph and text can be carried on the surface of a sheet material made of various materials such as a glass sheet, a film, a quartz sheet, a plastic sheet and the like.

10. A microlens array based projection system as claimed in claim 1, wherein: the micro-lens projection component of the system can be formed by bonding a micro-lens array 31, a micro-image and text 32 and a micro-lens array 33 into a whole; the micro-lens array 31 and the micro-lens array 33 can be arranged separately according to a required position relationship, the surface of the micro-lens array 31 and the micro-lens array 33 can be spherical, or can be a quadric surface or other aspheric surfaces, the arrangement mode of the micro-lens array 31 and the micro-lens array 33 can be a quadrilateral arrangement mode, a hexagonal arrangement mode or other arrangement modes, and the front-side and back-side light-tight areas of the micro-image 32 can be subjected to anti-reflection treatment including but not limited to black dyeing, black chromium plating and the like.