CN116568474A

CN116568474A - Reflective material mold with flat-top microprism array and preparation method thereof

Info

Publication number: CN116568474A
Application number: CN202180079680.9A
Authority: CN
Inventors: 黄志鹏; 梁桂德; 杨光; 朱庆金; 段明辉; 刘铠; 许明旗
Original assignee: Fujian Yueliang New Materials Co ltd
Current assignee: Fujian Yueliang New Materials Co ltd
Priority date: 2021-10-15
Filing date: 2021-12-29
Publication date: 2023-08-08
Also published as: CN113635495B; WO2023060775A1; CN113635495A; WO2023061150A1

Abstract

The invention discloses a reflective material mold with a flat-top microprism array and a preparation method thereof. The invention adopts a V-shaped knife to plane a micro V-shaped groove in a first direction, and after all the V-shaped grooves are planed in the first direction, the micro V-shaped groove is planed in the next planing direction, so that a reflective material mould with the same unit flat-top microprism array is constructed; the preparation method not only reduces the planing times, improves the production efficiency of the die and reduces the planing difficulty, but also the prepared flat-top microprism array reflective material has the excellent characteristics of meeting the large-angle incidence and observation conditions and keeping high retroreflection coefficient, is beneficial to improving the visibility of reflective signboards of road sections with large visual blind areas, such as high-speed entrance ramps, interchange bend guide ways and the like, and improves the safe driving coefficient.

Description

Reflective material mold with flat-top microprism array and preparation method thereof

Technical Field

The invention relates to the technical field of reflective materials, in particular to a reflective material mold with a flat-top microprism array and a preparation method thereof.

Background

Prism technology in the retroreflective material industry includes full prisms and large angle microprism retroreflective sheeting. The full prism is formed by removing non-reflective parts at three corners of a triangular pyramid and then splicing and combining again or reconstructing a full prism pyramid structure, and is a reconstruction of the corners of the triangular pyramid, so that a pyramid with two quadrilateral sides and one pentagonal side is formed; the existing method for preparing the full prism original mold is to complete the combination and assembly of the full prism unit pyramid or the reconstruction of the structure under the micron-level condition, and the preparation difficulty is extremely high from the aspect of maintaining the integrity and consistency of the pyramid.

The prior cube corner is a microcrystalline regular angle pyramid formed by injection molding or assembly molding through a construction die, and a pyramid with three quadrilateral side faces is formed. The large-angle pyramids different from the full prisms and the cube pyramids remain in the complete triangular pyramid state.

The reflecting film of the microprism with large angle, namely the reflecting film of the oblique prism, is to change the side surface shape of the pyramid and shift the tip point of the apex angle under the state of keeping the apex angle and the corner angle of the triangular pyramid so as to achieve the high retroreflection coefficient in the large angle direction. The number of sides of the pyramid is unchanged no matter how the shape of the side of the pyramid is changed, and the pyramid is still a three-sided triangle with different shapes.

The prior large-angle microprism reflecting film comprises an inclined triangular pyramid array microprism reflecting film with an apex angle inclined to one direction, triangular pyramid array microprism reflecting films with different inclination angles and the like, wherein the inclination angles of pyramid side surfaces of two sides of a V-shaped micro groove in the same direction are inconsistent. The preparation method of the original mold comprises the following steps:

different V-shaped cutters with the same inclination angles at two sides (the same V-shaped cutter with the same inclination angles at two sides and different inclination angles at two sides) or the same V-shaped cutters with different inclination angles at two sides (the same V-shaped cutter with different inclination angles at two sides and different inclination angles at two sides) are adopted.

The former needs to change different V-shaped cutters in different planing directions, and enters another planing direction after planing in the same direction is finished;

the latter requires the same V-shaped cutters but alternating planing in different directions. The preparation process of the two is complex.

Disclosure of Invention

The application provides a reflective material mold with a flat-top microprism array and a preparation method thereof, which solve the technical problems that in the prior art, when the mold is prepared, different V-shaped cutters need to be replaced in different planing directions or alternately planing in different directions is needed, and further the preparation process is complicated. The method comprises the steps of planing a micro V-shaped groove in a first direction by a V-shaped knife, and after all planing in the first direction, planing the micro V-shaped groove in the next planing direction, so as to construct a reflective material mold with the same unit flat-top microprism array.

The application provides a reflective material mold with a flat-top microprism array, wherein the reflective material mold is formed by the flat-top microprism array, the side surface of the flat-top microprism is trapezoid, and the top surface and the bottom surface of the flat-top microprism are parallel.

Further, the reflective material mold is formed from an array of unitary flat-top microprisms.

Further, the flat-top microprisms have 3 sides.

Further, the trapezoid is an isosceles trapezoid.

The preparation method of the reflective material mold with the flat-top microprism array comprises the following steps:

step (1) taking an original mold substrate, and carrying out roughness reduction pretreatment on the substrate to obtain a treated mold substrate;

step (2) taking the processed mold substrate, and planing the surface of the processed mold substrate along a first direction to obtain a planed mold substrate, wherein the planed mold substrate is provided with a plurality of Va-shaped grooves;

planing the surface of the die substrate along a second direction, wherein an included angle between the second direction and the first direction is 30-75 degrees, and the planed die substrate is provided with a plurality of Vb-shaped grooves;

and (4) planing the surface of the die substrate along a third direction, wherein an included angle between the third direction and the second direction is 30-75 degrees, and the planed die substrate is provided with a plurality of Vc-shaped grooves, so that the reflective material die with the flat-top microprism array is obtained.

Further, the method also comprises a pre-step, wherein the pre-step is performed before the step (1), and the pre-step is that

Step (a) calculating a planing distance: firstly designing a unit flat-top microprism, and then calculating the numerical value of each side length of the unit flat-top microprism;

step (b) simulation: substituting the numerical value obtained in the step (a) into a simulation system to obtain a corresponding simulation result, carrying out the step (1) when the result accords with 'the light spot is gathered in the wide angle range of the observation angle of 1 DEG, and the visible light spot is outside the observation angle range of more than 1 DEG', and continuing to return to the step (a) when the result does not accord.

Further, the method also comprises a step (A), wherein the step (A) can be implemented in any one of the step (2), the step (3) and the step (4); the step (A) specifically comprises the following steps:

the substrate is cleaned with the planing liquid without interruption during the planing process.

Further, the method also comprises a step (5), wherein the step (5) is implemented after the step (4), and the specific steps are as follows: and after planing, deburring the microprism type reflecting material mold of the flat-top microprism array, and performing ultrasonic cleaning.

Further, the specific steps of the roughness-reducing pretreatment are as follows: the roughness is reduced by adopting car leveling polishing, so that the roughness of the surface of the substrate is below 20 nm;

the depth H of the Va-shaped groove, the depth H of the Vb-shaped groove and the depth H of the Vc-shaped groove are 50um-150um;

the included angles of the Va-shaped groove, the Vb-shaped groove and the Vc-shaped groove are all 30-75 degrees.

One or more technical solutions provided in the present application have at least the following technical effects or advantages:

1. the method for preparing the complete pyramid is that the pyramid top is deepened along with the planing depth from a large flat top to a small flat top until the flat top disappears to a point to become a sharp top, and the required cutting depth is deeper. The planing times of the cutter of the preparation method of the reflective material die with the flat-top pyramid array are reduced to 1/2-9/10 of the original times, so that the preparation time of the original die is shortened, the preparation production efficiency of the original die is effectively improved, the wear rate of the cutter is reduced, and the service life of the cutter is prolonged.

2. When the manufactured reflective material working mould with the flat-top microprism array is used for planting cones, the reflective material mould is closely attached to the optical film to form a reflective layer structure, the depth of a concave cavity of a bright plate (intaglio) mould of the flat-top microprism array is shallower than that of a bright plate (intaglio) mould of the sharp-top microprism array, so that the filling of polymer resin of the optical film is more complete, the separation of the film and the mould is easier, the production efficiency is improved, and the integrity of the microprism units is further maintained.

3. Divergent retroreflection is the light that the same incident light can receive in a wide viewing angle range after being reflected by a reflector, indicating that the light is divergent retroreflected. Referring to fig. 11, light is radiated from a lamp, but after being reflected, the resulting visible view angle range is larger than the range of the vehicle. In principle, there are many incident light rays and many reflected light rays, but according to the wave-particle dichotomy of light and the roughness and physicochemical properties of the reflector, diffuse reflection and the like are generated on the light rays, and the light rays are lost. In the practical application process, the eye position of the driver receiving the light is different from the position of the car lamp emitting the light, namely the observation angle is different from the incident angle, so that a certain diffusion range is required after the light is reflected. The application improves the pyramid sharp angle with the triangular side surface into the flat-top pyramid with the trapezoidal side surface, so that the flat-angle pyramid with the trapezoidal side surface can form divergent retroreflection on incident light entering from a large angle obliquely in the pyramid, so that the large-angle retroreflection coefficient of the prism reflective film is greatly improved, and the problem that the retroreflection coefficient of the prism reflective film is severely reduced in a visible large-angle range is solved.

4. Solves the problem of directional sensitivity of the consistent cathode-anode stripe alternate balancing microprism reflecting film, and maintains the original appearance of the microprism reflecting film in a planar posture without light and shade alternate.

5. The diffusion effect of the flat-top microprism reflective film meets the requirement that a large-angle observation angle keeps reflective brightness with high retroreflection coefficient, is favorable for improving the visibility of reflective signs of road sections with large visual blind areas such as high-speed entrance ramp, interchange curve guide road and the like, and improves the safe driving coefficient.

6. In order to obtain more reflected light rays, the size of the pyramid needs to be increased, but after the size of the pyramid is increased, larger cone-planting force is needed when the pyramid is planted and stamped, the cone-planting force is increased, the pyramid is deformed, and the light rays run out of the field of view after deformation, so that brightness is lost. The flat-top structure can reduce the deformation of the pyramid, so that the pyramid of the die and the pyramid of the reflective original film keep higher consistency, namely the light retroreflection of the reflective film is as close as possible to the original die for the original purpose.

Drawings

FIG. 1 is a schematic illustration of the structural shaved dimensions of a flat-top microprism retroreflective material mold unit according to an embodiment of the present disclosure;

FIG. 2 is a schematic view of a dihedral angle deviation pyramid array with a flat top, with a portion of the sharp-tipped pyramid truncated;

FIG. 3 is a schematic diagram of a light structure when the light emitting direction is not identical to the incident direction;

FIG. 4 is a schematic view of the spot distribution with a diffuse effect at an observation angle of 1;

FIG. 5 is a schematic diagram showing the calculation result of the stress distribution simulated by simulation;

FIG. 6 is a schematic view of the planing structure of step 5 of the embodiment of the present application;

FIG. 7 is a schematic view of the planing structure of step 6 of the embodiment of the present application;

FIG. 8 is a schematic view of the planing structure of step 7 of the embodiment of the present application;

FIG. 9 is an electron microscopic view of the light reflecting material of comparative example 1 of the present application;

FIG. 10 is an electron microscope image of a retroreflective material made according to the method of the present embodiments;

fig. 11 is a schematic reflection diagram of a vehicle lamp.

Detailed Description

In order to better understand the above technical solution, the following detailed description will be given with reference to the specification and the specific embodiments.

A preparation method of a flat-top positive angle microprism reflecting material mold comprises the following steps:

step (1): calculating planing distance, designing a flat-top microprism unit, and calculating data of the flat-top microprism unit based on the sharp-top microprism unit, wherein the data are as follows

Referring to fig. 1, the angles of the triangles on the bottom surface of the regular pyramid are designed to be 60 °, namely = a = B = C = 60 °, the triangles on the bottom surface of the regular pyramid are equilateral triangles, the side length is L, and the height is D; the triangle on the side surface of the regular angle pyramid is an isosceles right triangle, and the edge length of the triangle is L.sin 45 degrees; the height of the steeple regular angular pyramid is h. The side length of the triangle at the top of the flat-top regular-angle pyramid is l; the height of the flat-top regular-angle pyramid is H. The cutter is a V-shaped cutter, and the inclination angles of the two sides of the V-shaped cutter are theta.

From the conditions provided above, we can obtain the following formula:

L＝D/sin60° ①

h＝L/2·tan45·sin(90-θ)°＝L/2·tan45·cosθ ②

the same principle can be obtained:

h-H＝l/2·tan45·cosθ，

and then can be derived:

l＝2(h-H)/(tan45°·cosθ)＝(L·tan45°·cosθ-2H)/(tan45°·cosθ)＝L-2H/(tan45°·cosθ) ③

substituting formula (1) into formula (3) to obtain:

l＝D/sin60-2H/(tan45°·cosθ) ④

to sum up, the triangular area S of the flat top surface of the positive-angle pyramid can be obtained _d Is that

S _d ＝1/2L·D-1/2(l+L)·H·tanθ·3＝D ² /2sin60°-(D/sin60°-H/tan45°·cosθ)·H·tanθ·3 ⑤

On the basis of the conclusion, selecting a V-shaped cutter with angles of inclination theta at two sides, wherein theta is 35.25 degrees, and D is 250um, and obtaining the V-shaped cutter:

L＝2·D·cot60°＝288.67um

h＝L/2·tan45°·cosθ＝118.35um

in actual production, in the cone-planting process of an optical film, due to the thermal and mechanical factors, a cone structure of a metal mold is transferred to a cone of an organic optical material reflective original film to generate extremely small deformation, and the original film cone is flat and small relative to the mold cone, so that a numerical value obtained by a calculation result is corrected in simulation and simulation, and the numerical value is applied to modeling, namely L=290 um. When H < H, a flat-topped positive pyramid is produced, so taking h=110um, then l=l-2H/(tan 45 °. Cos θ) =21.7 um, taking l=22um.

Step (2): constructing a pyramid structure simulation by geometrical optical calculation software, setting a light incident angle beta=4° for analysis, and truncating a dihedral angle deviation pyramid (according to the numerical correction result in the step (1), the included angle of three side surfaces of the pyramid is not completely equal to 90 °) array with a plane top of a peak pyramid part with the bottom side length l of 22um, as shown in fig. 2; the light ray emitting direction is not identical to the incident direction, as shown in fig. 3; except that the observation angle range becomes large, and at the same time, a part of light rays generate a diffusion effect of 180 degrees in a larger range, as shown in fig. 4.

The simulation shows that under the ideal condition of the optical film and the reflective layer polyester resin material (namely, the physicochemical parameters of the film layer such as light transmittance and refractive index are optimal, the surface is smooth without diffuse reflection and other factors to cause light loss), the microprism reflective film with flat-topped dihedral angle deviation pyramid array has the advantages that light spots gather in the wide angle range of 1 degree observation angle and visible light spots are outside the observation angle range of more than 1 degree observation angle, as shown in fig. 4.

Step (3): simulation and comparison analysis are carried out on the cone implantation process through finite element analysis software: the cone planting process, hot pressing and cone planting or UV resin photocuring cone planting are completed under the condition of higher process temperature, and as the pyramid surface pyramid structure of the gravure pyramid mould is horn-shaped, the pyramid is wide in upper part and narrow in lower part, and the pyramid with the same size is more stressed at the tip angle than the flat top angle in the process of filling high polymer resin, and the pyramid is easier to deform. Through simulation, the calculation result of the stress distribution is shown in fig. 5, and it can be seen from the graph that the flat top can reduce the stress of the pyramid (the deeper the color is, the larger the numerical value is), the stress at the top of the sharp-top pyramid is much greater than that of the flat-top pyramid, the larger stress can lead to large deformation of the pyramid, dihedral angle deviation (the included angle between the pyramid sides deviates from 90 degrees) is generated, the light propagation direction is changed, and the brightness of the film is reduced. Therefore, the flat-top microprisms are further described to help reduce the small deformation of the pyramid direction and stabilize the original brightness of the reflective film.

Furthermore, the depth of the concave cavity of the flat-top pyramid is shallower than that of the concave cavity of the sharp-top pyramid, and the flat-top pyramid is easy to form a complete structure by separating and analyzing from a hot-press filling film (optical film with pyramid array) die (metal die with pyramid array), while the sharp-top pyramid is difficult to form a complete structure when filling, and the sharp-top part is easy to be damaged when the film die is separated, so that the complete triangular pyramid is deformed or damaged and generally does not reflect light.

The above results are consistent with "the light spot is concentrated in the wide angle range of 1 ° observation angle, and the visible light spot is outside the observation angle range of more than 1 °, and the planing is started.

Step (4): taking an original mold substrate, and adopting car leveling polishing to reduce the roughness of the original mold substrate so that the roughness of the surface of the substrate is below 20 nm;

step (5): referring to fig. 6, a processed mold substrate is taken, and planing is performed on the surface of the processed mold substrate along a first direction, so that a planed mold substrate is obtained, wherein the planed mold substrate is provided with a plurality of Va-shaped grooves, the depth of each Va-shaped groove is 110um, and the distance between every two adjacent Va-shaped grooves is 250um;

step (6): referring to fig. 7, planing is performed on the surface of the mold substrate along a second direction, wherein an included angle between the second direction and the first direction is 60 degrees, the planed mold substrate is provided with a plurality of Vb-shaped grooves, the depth of each Vb-shaped groove is 110um, and the distance between every two adjacent Vb-shaped grooves is 250um;

step (7): referring to fig. 8, planing is performed on the surface of the mold substrate along a third direction, wherein an included angle between the third direction and the second direction is 60 degrees, an included angle between the third direction and the first direction is 120 degrees, a plurality of Vc-shaped grooves are formed on the planed mold substrate, the depth of each Vc-shaped groove is 110um, and the distance between every two adjacent Vc-shaped grooves is 250um;

and (3) in the planing process of the step (4), the step (5), the step (6) and the step (7), the substrate is washed by using planing liquid continuously, burrs are removed after the planing is finished, and ultrasonic cleaning is carried out to obtain the flat-top regular-angle pyramid reflecting material die.

Experimental test

The flat-top regular-angle pyramid reflecting material die prepared by the embodiment of the application is adopted, and the flat-top regular-angle pyramid reflecting material die is transferred onto an optical film through hot-pressing cone implantation to prepare the micro-prism reflecting original film. Meanwhile, the prior sharp-topped pyramid array microprism reflective original film with the same unit microprism size is used as a control group, and experimental data are obtained as follows:

the method comprises the steps of preparing original dies of a sharp-top and flat-top regular-angle pyramid array by planing the bottom surface of an equilateral triangle pyramid with planing direction included angles (angle A, angle B and angle C) equal to 60 degrees and side length L=290 um through a V-shaped knife with an inclination angle theta=30.25 degrees, and transferring the structures of the two original dies to an optical film through hot-pressing cone implantation to prepare the micro-prism reflection original film. The Shade PC film ShatePC-801 and LonghuaaPC-8013R were used as comparative examples 1 and 2, respectively. The experimental results of comparative example 1 are shown in table 1, the results of comparative example 2 are shown in table 2, and the results of examples of the present application are shown in table 3:

as can be seen from the data in table 1, the measured values of the retroreflection coefficient R at the observation angles of α=0.2°, 0.5 ° and 1 ° reach the standard rates of 100%, 85.41% and 0%, respectively;

average standard reaching rates are 100%, 100% and 0% respectively.

When the incident angle beta= -4 degrees, the observation angle alpha=0.2 degrees gradually becomes larger, and the retroreflection coefficients at alpha=0.5 degrees and 1 degrees are respectively reduced by 71.87 percent and 96.29 percent.

When the incident angle β=15°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 74.94% and 96.87%, respectively.

When the incident angle β=30°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 65.50% and 99.03%, respectively.

As can be seen from the data in table 2, the measured values of the retroreflection coefficient R at the observation angles of α=0.2°, 0.5 ° and 1 ° reach the standard rates of 100%, 89.58% and 39.58%, respectively;

average standard reaching rates are 100%, 100% and 33.33% respectively.

When the incident angle beta= -4 degrees, the observation angle alpha=0.2 degrees gradually becomes larger, and the retroreflection coefficients at alpha=0.5 degrees and 1 degrees are respectively reduced by 50.68 percent and 94.41 percent.

When the incident angle β=15°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 58.02% and 92.46%, respectively.

When the incident angle β=30°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 55.69% and 98.03%, respectively.

As can be seen from the data in table 3, the measured values of the retroreflection coefficient R at the observation angles of α=0.2°, 0.5 ° and 1 ° reach the standard rates of 100%, 86.11% and 88.89%, respectively;

average standard reaching rates are 100%, 100% and 100% respectively.

When the incident angle beta= -4 degrees, the observation angle alpha=0.2 degrees gradually becomes larger, and the retroreflection coefficients at alpha=0.5 degrees and 1 degrees are respectively reduced by 40.50 percent and 77.32 percent.

When the incident angle β=15°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 36.21% and 82.21%, respectively.

When the incident angle β=30°, the observation angle α=0.2° gradually increases, and the retroreflection coefficient at α=0.5° and 1 ° decreases by 40.52% and 76.78%, respectively.

In summary, for a positive angle pyramid, comparison of three sets of data from comparative example 1, comparative example 2, and this application example, in a small angle observation angle or small angle incidence angle range, shows that the pyramid that remains the peak portion of the intact pyramid has a higher retroreflection coefficient than a flat-topped pyramid, whereas the light loss of the intact pyramid is severe in a large angle range, the retroreflection coefficient drops sharply, and the retroreflection coefficient falls to a level that does not reach the standard in a standard large angle range.

The microprisms obtained in comparative examples 1, 2 and examples of the present application were observed under an electron microscope, wherein the electron microscope images of comparative examples 1, 2 are shown in fig. 9 (the electron microscope images of comparative examples 1, 2 observed with naked eyes are not different, and thus only the image of comparative example 1 is placed), and the electron microscope images of examples of the present application are shown in fig. 10. Through the observation of an upper electron microscope image, the flat-top positive angle microprism reflecting material in the embodiment of the application finds that, due to the existence of the flat top, when incident light rays particularly irradiate into the pyramid from the front side within a small angle range, the positions of the plane where the flat top is irradiated are less because of total reflection, and most of the light rays penetrate through the past and are not reflected back to the detector, so that obvious non-reflecting points appear in the middle, but the proportion of the non-reflecting positions of the flat top in the whole pyramid (the pyramid size L=290 um) is smaller.

The above description is illustrative of the embodiments using the present teachings, and is not intended to limit the scope of the present teachings to any particular modification or variation of the present teachings by those skilled in the art.

Claims

The reflecting material mold with the flat-top microprism array is characterized in that the reflecting material mold is formed by the flat-top microprism array, the side surface of the flat-top microprism is trapezoid, and the top surface and the bottom surface of the flat-top microprism are parallel.
The retroreflective material mold having a flat-top microprism array of claim 1 wherein the retroreflective material mold is formed from an array of unitary flat-top microprisms.
The retroreflective material mold of claim 1 having an array of flat-top microprisms, wherein the flat-top microprisms have 3 sides.
The retroreflective material mold with flat-top microprism array of claim 1 wherein the trapezoid is an isosceles trapezoid.
The preparation method of the reflective material mold with the flat-top microprism array is characterized by comprising the following steps:

step (1) taking an original mold substrate, and carrying out roughness reduction pretreatment on the substrate to obtain a treated mold substrate;

step (2) taking the processed mold substrate, and planing the surface of the processed mold substrate along a first direction to obtain a planed mold substrate, wherein the planed mold substrate is provided with a plurality of Va-shaped grooves;

planing the surface of the die substrate along a second direction, wherein an included angle between the second direction and the first direction is 30-75 degrees, and the planed die substrate is provided with a plurality of Vb-shaped grooves;

and (4) planing the surface of the die substrate along a third direction, wherein an included angle between the third direction and the second direction is 30-75 degrees, and the planed die substrate is provided with a plurality of Vc-shaped grooves, so that the reflective material die with the flat-top microprism array is obtained.
The method of claim 5, further comprising a pre-step of performing the pre-step (1) before the step of

Step (a) calculating a planing distance: firstly designing a unit flat-top microprism, and then calculating the numerical value of each side length of the unit flat-top microprism;

step (b) simulation: substituting the numerical value obtained in the step (a) into a simulation system to obtain a corresponding simulation result, carrying out the step (1) when the result accords with 'the light spot is gathered in the wide angle range of the observation angle of 1 DEG, and the visible light spot is outside the observation angle range of more than 1 DEG', and continuing to return to the step (a) when the result does not accord.
The method of claim 5, further comprising a step (a) which can be performed at any one of the steps (2), (3) and (4); the step (A) specifically comprises the following steps:

the substrate is cleaned with the planing liquid without interruption during the planing process.
The method of claim 5, further comprising the step of (5), wherein the step of (5) is performed after the step of (4), and the specific steps of: and after planing, deburring the microprism type reflecting material mold of the flat-top microprism array, and performing ultrasonic cleaning.
The method of claim 5, wherein the method further comprises the steps of,

the specific steps of the roughness reduction pretreatment are as follows: the roughness is reduced by adopting car leveling polishing, so that the roughness of the surface of the substrate is below 20 nm;

the depth H of the Va-shaped groove, the depth H of the Vb-shaped groove and the depth H of the Vc-shaped groove are 50um-150um;

the included angles of the Va-shaped groove, the Vb-shaped groove and the Vc-shaped groove are all 30-75 degrees.