WO2015196326A1

WO2015196326A1 - Neutral density filter having multiple film layers, manufacturing device thereof and manufacturing method therefor

Info

Publication number: WO2015196326A1
Application number: PCT/CN2014/080488
Authority: WO
Inventors: 孙义昌
Original assignee: 孙义昌
Priority date: 2014-06-23
Filing date: 2014-06-23
Publication date: 2015-12-30

Abstract

A neutral density filter having multiple film layers, a manufacturing device thereof and a manufacturing method therefor. The neutral density filter comprises a substrate (1000) plated with a plurality of film layers, the film layers comprise antireflection films and metal films that are laminated, and the refractive index of the materials forming the antireflection films is higher than 1.3. The manufacturing device of the neutral density filter having multiple film layers comprises a vacuum chamber (10), a film plating umbrella (11) and a power source (12). The film plating umbrella (11) is fixed to the top of the cavity of the vacuum chamber (10), a rotary shaft of the film plating umbrella (11) is connected to the power source (12), and the bottom of the cavity of the vacuum chamber (10) is provided with two film plating material sources (14, 15) that are located below the film plating umbrella (11). A correction plate (13) is fixed in the vacuum chamber (10), and one end of the correction plate (13) is located on the same side of the two film plating material sources (14, 15). The manufacturing method for the neutral density filter having multiple film layers comprises the steps of: (1) placing a substrate in the vacuum chamber (10), pumping the vacuum chamber (10) to a preset vacuum degree, and fixing the correction plate (13) in the vacuum chamber (10); and (2) driving the film plating umbrella (11) to rotate by using the power source (12), wherein the two film plating material sources (14, 15) are used for evaporation of the film layers in an alternating mode, and the film layers are sequentially laminated according to the preset optical thickness and a preset order.

Description

Neutral gray-scale dimming filter of multilayer film layer, manufacturing device thereof and manufacturing method thereof

The present invention relates to a neutral grayscale dimming filter, and more particularly to a medium gray fixed value dimming filter and a medium gray gradient dimming filter and a manufacturing apparatus therefor. Background technique

The neutral gray filter is an energy splitting element that balances light attenuation. It is mainly used to filter light during photographic photography. It has the advantages of simple structure and wide wavelength range. The neutral gray filter includes a Neutral Density Filter (ND Mirror) and a Graduated Neutral Density Filter (Journey Neutral Density Filter).

The ND mirror is mainly used to reduce the amount of exposure of the camera. When the subject is bright, the D mirror is required to reduce the exposure. The ND mirror filter is non-selective to the light. The ND mirror is equally and uniform in reducing the light of different wavelengths. It only acts to attenuate the light and has no effect on the color of the original object. The optical density does not change with position, and the overall part is uniform. The optical density of the GND mirror varies with position and has different darkness variations, ie different optical densities. The GND mirror does not change the color balance of the picture, but it can change the contrast of the light. For example, in the case of a large difference in light, if the light is strongly exposed on one side, the weak side is underexposed; if the weak side is exposed accurately, the strong side is overexposed. This problem can be solved by adding a GND mirror in front of the lens.

When producing ND mirrors or 'GD mirrors, the deformation of the resin sheet or the adhesive layer may affect the image quality, or the phenomenon of ghosting during use due to high reflectance. Take the GND mirror as an example, including the following four production methods. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a transmittance spectrum curve of a GND mirror manufactured by a resin dyeing method, a glass lamination method, and a medium gray glass bonding method in the prior art. As shown in FIG. 1, curve 1 represents a light transmittance spectrum curve of a GND mirror manufactured by a resin dyeing method, and resin dyeing is required to be deformed in a high-temperature liquid during the dyeing process and the resin lens itself is easily deformed, thereby causing deformation of the resin sheet, thereby It is difficult to achieve high definition images that affect the imaging quality of photographic cameras. At the same time, due to the dispersion problem of the dye, the light cannot be balanced and attenuated. It can be seen from the spectrum that the transmittance has increased significantly since the wavelength of 650 nm, which is the main cause of redness in photography. Curve 2 represents the transmittance spectrum curve of the GND mirror manufactured by the glass lamination method, and the glass clip film is composed of two pieces of glass intermediate clips, and has a disadvantage of having a large thickness in addition to the above disadvantages of resin dyeing. Curve 3 represents the middle gray glass glue The light transmittance spectrum curve of the GND mirror manufactured by the method, after the gray glass and the colorless transparent glass are glued, is obliquely ground, so that the medium gray glass is changed in thickness to achieve the balance attenuation effect. Due to the deformation caused by the glue layer, the imaging quality of the photographic image is affected and the true high transmittance of the high transmission region cannot be achieved and the true balance of the light cannot be attenuated. 2a is a schematic view showing a transmittance spectrum curve of a GND mirror manufactured by a vacuum neutral metal film method in the prior art. Fig. 2b is a schematic view showing a reflectance spectrum curve of a GND mirror manufactured by a vacuum neutral metal film method in the prior art. As shown in Fig. 2a, curve 1 represents the transmittance spectrum curve, as shown in Fig. 2b, curve 1 represents the reflectance spectrum curve, and the vacuum neutral metal film process better solves the problem of affecting imaging quality and is ideal. The light balance attenuation function. However, because of the high reflectivity, it is easy to produce ghosts during use. Summary of the invention

The technical problem to be solved by the present invention is to provide a neutral gray-scale dimming filter of a multilayer film layer and a manufacturing method thereof, which can produce an ND mirror and a GND mirror with good light balance attenuation effect and low reflectivity. At the same time, the manufacturing process does not affect the image quality.

In order to achieve the above object, the present invention provides a neutral grayscale dimming filter of a multilayer film layer and a method of fabricating the same, comprising a substrate, the substrate being plated with a plurality of film layers, the film layer comprising a laminate The antireflection film and the metal film, the constituent material of the antireflection film has a refractive index of more than 1.30.

Preferably, the constituent material of the anti-reflection film comprises at least one selected from the group consisting of A1 ₂ 0 ₃ , A1F ₃ , BeO, CaF ₂ , CeF ₃ , CeO ₃ , Cr ₂ 0 ₃ , Dy ₂ 0 ₃ , Gd ₂ 0 ₃ , Hf0 ₂ , Ho ₂ 0 ₃ , ln ₂ 0 ₃ , : LaF ₃ , MgF ₂ , MgO, NiO, Nd ₂ 0 ₃ ,

_{_{Sn0 3, SiO, Si0 2,}} Sm 2 0 3, Ti0 2, Ta 2 0 5, Thi0 2, compound or a mixture composed of the compound of Zr0 _2.

Preferably, the constituent material of the metal film includes at least one metal element selected from the group consisting of Al, Ag, Cr, Ni, Au, Cu, Fe, Zn, Sn, Mo or an alloy composed of the above-mentioned metal element.

Preferably, the substrate is plated with at least two layers of the film layer.

Preferably, the optical thickness of the film of the anti-reflection film ranges from 1 to 300 nm, and the optical thickness of the film of the metal film ranges from 1 to 320 nm.

Preferably, the reflectance ranges from 1.50% to 2.30% in the wavelength range of 420 to 680 nm, and the transmittance ranges from 47.8% to 51.3%.

Preferably, in the interval of wavelength _420 to 680 nm, the range of the reflectance at the maximum end of the attenuation is 2.5% to 3.1%, and the range of the transmittance is 11.45% to 12.06%, and the range of the reflectance at the minimum end of the attenuation is 1.5%~2.3%, the range of transmittance is 47.8%~96.3% ₀

Preferably, the apparatus for manufacturing a neutral grayscale filter of a multilayer film layer comprises: a vacuum chamber, a coated umbrella and a power source, the coated umbrella being fixed on the top of the cavity of the vacuum chamber, the coating The rotating shaft of the umbrella is connected to the power source, and the bottom of the cavity of the vacuum chamber is provided with two symmetrically distributed sources of coating materials, two of which are located under the coated umbrella; the correction plate is fixed in the vacuum chamber. One end is located on the same side of the two coated materials.

Preferably, the apparatus for manufacturing a neutral gray-scale dimming filter of a multi-layer film layer further includes a baffle plate, wherein the baffle plate is provided with a plurality of symmetrically distributed gradation holes, and the gradation hole has a blade shape .

Preferably, the method for manufacturing a neutral gray-scale dimming filter of a multi-layer film layer comprises the steps of: (1) placing the substrate in the vacuum chamber, and pumping the vacuum chamber to a vacuum pump Predetermining the degree of vacuum, fixing the correction plate in the vacuum chamber; (2) the power source drives the coating umbrella to rotate, and the two coating materials alternately vapor-deposit the film layer, wherein the film layer is a predetermined thickness and a predetermined order, in addition, preferably, a method of manufacturing a neutral gray scale filter of a multilayer film layer, wherein the correction plate in the step (1) is removed, in the step (1) Between the step (2) and the step (2), the step of installing the baffle under the film umbrella is also included.

As can be seen from the above description and practice, the neutral grayscale filter of the multilayer film provided by the present invention and the manufacturing method thereof, wherein the neutral grayscale filter of the multilayer film layer is provided with anti-reflection The film is separated by a compound layer having a refractive index higher than 1.30, and the multilayer anti-reflection film is laminated with the multilayer metal film, so that the reflectance of the ND mirror and the GND mirror is low, and the light balance can be attenuated; The ND mirror and the GND mirror manufactured by the method for manufacturing the neutral gray-scale dimming filter of the multi-layer film have low reflectance, good effect on light balance attenuation, and the manufacturing process does not affect the image quality; The same plating device can be used with the correction plate or the baffle plate to manufacture the ND mirror and the GMD mirror respectively. Fourthly, the baffle plate can make the plated neutral metal show a thin thickness change on the substrate, thereby achieving the gradual effect. DRAWINGS

The above features and technical advantages of the present invention will become more apparent and understood from the <RTIgt; In the drawing,

1 is a schematic view showing a transmittance spectrum curve of a GND mirror manufactured by resin dyeing, glass lamination, and medium gray glass bonding in the prior art; 2a is a schematic view showing a transmittance spectrum curve of a GND mirror manufactured by a vacuum neutral metal film method in the prior art;

2b is a schematic view showing a reflectance spectrum curve of a GND mirror manufactured by a vacuum neutral metal film method in the prior art;

3a is a schematic view of an ND mirror of a neutral grayscale filter of a multilayer film layer according to an embodiment of the present invention;

Figure 3b is a schematic view of the ND mirror plating apparatus of the neutral gray scale filter of the multilayer film layer shown in Figure 3a;

4 is a schematic view of a baffle plate of a GND mirror of a neutral gray scale filter of a multilayer film according to still another embodiment of the present invention;

Figure 5a is a schematic illustration of the spectral curve of the transmittance of the GKD mirror of the neutral grayscale filter of the multilayer film of Figure 4;

Figure 5b is a graphical representation of the spectral curve of the reflectivity of the GND mirror of the neutral gray scale filter of the multilayer film of Figure 4. ' Reference mark:

Substrate: 1000; manufacturing device 100;

10: vacuum chamber; 11: coated umbrella; 12: power source; 13: correction plate;

14: coating material source; 15: coating material source; 16: baffle; 161: gradient hole; - specific embodiment

The above described objects, features and advantages of the present invention will become more apparent from the aspects of the appended claims.

The neutral gray-scale dimming filter of the multilayer film layer comprises a substrate on which a plurality of film layers are plated, the film layer comprises a laminated anti-reflection film and a metal film, and the refractive index of the constituent material of the anti-reflection film is greater than 1.30.

Preferably, the constituent material of the anti-reflection film includes at least one selected from the group consisting of A1 ₂ 0 ₃ , A1F ₃ , BeO, CaF ₂ , CeF ₃ , CeO ₃ , Cr ₂ 0 ₃ , Dy ₂ 0 ₃ , Gd ₂ 0 ₃ , Hf0. ₂ , Ho ₂ 0 ₃ , ln ₂ 0 ₃ , LaF ₃ , MgF ₂ , MgO, MO, Nd ₂ 0 ₃ , Pb ₆ 0 „ Sn0 ₃ , SiO, Si0 ₂ , Sm ₂ 0 ₃ , Ti0 ₂ , Ta ₂ 0 _{5, Thi0} _2, compound mixture composed of the above compound or Zr0 _2. antireflection film may be a compound having a refractive index greater than 1.30, may be a mixture of 1.30 greater than the refractive index of compounds of general. Preferably, the constituent material of the metal film includes at least one metal element selected from the group consisting of Al, Ag, Cr, Ni, Au, Cu, Fe, Zn, Sn, Mo or an alloy composed of the above-mentioned metal element. The metal film may be a single element of a metal or an alloy of a plurality of metal elements.

Preferably, the substrate is plated with at least two film layers. Preferably, the optical thickness of the film of the anti-reflection film ranges from 1 to 300 nm, and the optical thickness of the film of the metal film ranges from 1 to 320 nm.

In the present embodiment, an ND mirror having an attenuation of 88% is taken as an example, and Fig. 3a is a schematic view of a M) mirror of a neutral gray-scale dimming filter of a multilayer film layer according to an embodiment of the present invention. As shown in FIG. 3a, there are ten film layers on the substrate 1000, the single film layers in the first film layer to the eighth film layer are anti-reflection films, the double film layers are metal films, the ninth film layer and the tenth layer. The film layer is an anti-reflection film. The composition, optical thickness and distribution of the film layer on the substrate 1000 are shown in Table 1 -. - Table 1 is a table of ten layers of layers deposited on the substrate.

Table 1 Table of the ten layers of layers deposited on the substrate

Next, a manufacturing apparatus of a multi-layer coated neutral gray reduction filter will be described. The manufacturing apparatus of the neutral gray reduction filter includes a manufacturing apparatus of the D mirror and a manufacturing apparatus of the GND mirror.

First, introduce the manufacturing equipment of the ND mirror. Fig. 3b is a schematic view showing the apparatus for manufacturing the ND mirror of the neutral gray scale filter of the multilayer coating shown in Fig. 3a.

As shown in FIG. 3b, the manufacturing apparatus 100 of the ND mirror includes a vacuum chamber 10, a coated umbrella 11 and a power source 12, and a coated umbrella 1 is fixed to the top of the cavity of the vacuum chamber 10, and a rotating shaft of the coated umbrella 1 is connected with a power source 12 The power source 12 drives the coated umbrella 11 to rotate, and the power source 12 is located outside the vacuum chamber 10, and the vacuum chamber The bottom of the cavity of the 10 is provided with two symmetrically distributed coating material sources, namely a coating material source 14 and a coating material source 15, respectively, and the coating material source 14 and the coating material source 15 are located below the coated umbrella 11. The correction plate 13 is fixed in the vacuum chamber 10, and the correction plate 13-end is located on the same side of the coating material source 14 and the coating material source 15, and the uniformity of the coating material source 14 and the coating material source 15 can be corrected.

The following describes the manufacturing equipment of the GND mirror. 4 is a schematic view of a baffle plate of a GND mirror of a neutral gray reduction filter of a multi-layer coating according to still another embodiment of the present invention.

The main difference between the manufacturing apparatus and the manufacturing of the GND mirror is that the manufacturing apparatus for manufacturing the GND mirror does not include the correction plate 13, but the baffle 16 is mounted under the coated umbrella 11, about 0.1 to 50 cm from the coated umbrella 11. A baffle 16 is provided, and the distance between the baffle 16 and the coated umbrella 11 will affect the decay rate of the coating. As shown in Fig. 4, the baffle 16 has a circular cross section, and may be 60° or 120° or 0 to 360° - a fan shape at any angle. The baffle 16 allows the plated neutral metal to exhibit a thin change in the substrate to achieve a gradual effect. It is also possible to cause the plated neutral metal film to exhibit a thin thickness change by means of a motor dragging the baffle parallel to the substrate or other occlusion means.

Next, a method of manufacturing a neutral gray scale filter of a multilayer film layer will be described. The neutral grayscale filter includes an ND mirror and a GND mirror.

First, introduce the manufacturing method of the ND mirror. Figure 3b is a schematic view of the ND mirror plating apparatus of the neutral gray scale filter of the multilayer film layer shown in Figure 3a.

3b, the first step, the substrate 1000 is placed within the vacuum chamber 10, the vacuum chamber 10 using a vacuum pump evacuated to a predetermined degree of vacuum, preferably, a predetermined degree of vacuum chamber was 3.5 X 10_ ³ Pa or 9.0X l (T ³ Pa. Fixing the correction plate 13 in the vacuum chamber 10; - In the second step, the power source 12 drives the film umbrella 11 to rotate, and the film layer source 14 and the film layer source 15 are alternately vapor-deposited. The film layers are formed on the substrate 1000, and the film layers are sequentially laminated in a predetermined optical thickness and a predetermined order. In the present embodiment, the film layers are laminated in the optical thickness and order shown in Table 1.

Next, the manufacturing method of the GN mirror is introduced. Fig. 4 is a perspective view showing a baffle plate of a GND mirror of a neutral gray scale filter of a multilayer film according to still another embodiment of the present invention.

As shown in Fig. 4, the main difference between the manufacture of the GND mirror and the manufacture of the D mirror is that the correction plate 13 in the step (1) is removed, and the following steps are added between the steps (1) and (2), in the film. A baffle 16 is installed below the layer umbrella 11, and a baffle 16 is disposed at about 0.1 to 50 cm from the film umbrella 11. The distance between the baffle 16 and the film umbrella 11 will affect the attenuation rate of the film layer. The baffle 16 can cause the plated neutral metal to be on the substrate 1000 A thin and thick change is made to achieve a gradual effect. It is also possible to make the plated neutral metal film exhibit a thin thickness change by means of a motor dragging the baffle parallel to the substrate or other shielding means.

The transmittance and reflectance of the ND mirror and the GND mirror manufactured by the method of manufacturing the neutral gray reduction filter of the multilayer film layer are described below.

Preferably, in the interval of wavelength 420 to 680 nm, the reflectance ranges from 1.50% to 2.30%, and the transmittance ranges from 47.8% to 51.3%.

Preferably, in the interval of 420 to 680 nm, the range of the reflectance at the maximum end of the attenuation is 2.5% to 3.1%, and the range of the transmittance is 11.45% to 12.06%, and the range of the reflectance at the minimum end of the attenuation is

I.5%~2.3%, the transmittance range is 47.8%~96.3%.

The D-mirror plated by the spectrometer is concluded as follows: In the wavelength range of 420 nm to 680 nm, the transmittance is the highest at a wavelength of 580 nm, and the maximum transmittance is 51.3%. At a wavelength of 440 nm, the transmittance is the smallest. The minimum transmittance is 47.8%, and the average transmittance is 50.5% in the range of 420 nm to 680 nm. In the interval of 420nm-^80nm, the reflectance is the largest at a wavelength of 420nm, the maximum reflectance is 2.3%, the reflectance is the smallest at a wavelength of 493nm, the minimum reflectance is 1.5%, and M is in the range of 420nm-680nm. The average transmission rate is 1.8%.

Figure 5a is a graphical representation of the spectral curve of the transmittance of a GM mirror of a neutral gray scale filter of the multilayer film of Figure 4. Figure 5b is a graphical representation of the spectral curve of the reflectivity of the GND mirror of the neutral gray scale filter of the multilayer film of Figure 4.

As shown in Fig. 5a, the GND mirror is tested by spectrometer. The conclusion is as follows: Curve 1 represents the maximum attenuation at the wavelength of 420 nm to 680 nm, and the maximum transmittance at the wavelength of 580 nm. The rate is 12.06%, the transmittance is the smallest at the wavelength of 440nm, and the minimum transmittance is

II.45%, and in the visible region of wavelength 420nm-680nm, the average transmittance is 11.95%;

As shown in Fig. 5b, curve 1 represents the reflectance at the maximum end of the attenuation in the interval of 420 nm to 680 nm, the maximum reflectance at a wavelength of 420 nm, the maximum reflectance of 3.1%, the minimum reflectance at a wavelength of 493 nm, and the minimum reflectance. It is 2.5%, and the average transmittance is 1.8% in the range of 420 nm to 680 nm.

In the wavelength range of 420 nm to 680 nm, the transmittance at the minimum end of the attenuation is the largest at a wavelength of 580 nm, and the maximum transmittance is 96.3%. The transmittance at the minimum end of the attenuation is the smallest at a wavelength of 440 nm, and the minimum transmittance is 47.8%. The average transmittance was 50.5% in the range of 420 nm to 680 nm. At wavelength In the interval from 420nm to 680nm, the reflectance at the minimum end of the attenuation is the largest at a wavelength of 420nm, the maximum reflectance is 2.3%, and the reflectance at the minimum end of the attenuation is the smallest at a wavelength of 493nm, the minimum reflectance is 1.5%, and at a wavelength of 420nm-680nm. Within the interval, the average transmission rate was 1.8%.

The neutral gray-scale dimming filter of the multilayer film layer provided by the embodiment provided by the present invention and the manufacturing method thereof, wherein the neutral gray-scale dimming filter of the multi-layer film layer is provided with an anti-reflection film. The metal element layer is separated by a compound layer having a refractive index higher than 1.30, and the multilayer anti-reflection film is laminated with the multilayer metal film, so that the reflectance of the ND mirror and the GND mirror is low, and the light balance can be attenuated; The ND mirror and the GND mirror manufactured by the method for manufacturing the neutral gray-scale dimming filter of the multi-layer film have low reflectance, good effect on light balance attenuation, and the manufacturing process does not affect the image quality; The device can be used with the correction plate or the baffle to manufacture the D mirror and the GND mirror respectively. Fourthly, the baffle can make the plated neutral metal show a thin thickness change on the substrate to achieve the gradual effect.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical scope of the present invention. All should be covered by the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Claim

A neutral gray-scale dimming filter for a multilayer film layer, comprising: a substrate, wherein the substrate is plated with a plurality of film layers, the film layer comprising a laminated anti-reflection film and a metal The film, the constituent material of the anti-reflection film has a refractive index greater than 1.30.

The neutral gray-scale dimming filter of the multilayer film layer according to claim 1, wherein the constituent material of the anti-reflection film comprises at least one selected from the group consisting of A1 ₂ 0 ₃ , A1F ₃ , BeO , CaF ₂ , CeF ₃ , CeO ₃ , Cr ₂ 0 ₃ , Dy ₂ 0 ₃ , Gd ₂ 0 ₃ , Hf0 ₂ , Ho ₂ 0 ₃ , ln ₂ 0 ₃ , LaF ₃ , MgF ₂ , MgO, NiO, Nd ₂ _{_{0 3, Pb 6 0 ",}} Sn0 3, _{_{_{Si〇, Si0 2, Sm 2 0 3}}} , Ti0 2, Ta compound or a mixture composed of the compound _{_{_{2 0 5, Thi0 2, Zr0}}} 2 in.

The neutral gray-scale dimming filter of the multilayer film layer according to claim 1, wherein the constituent material of the gold-based film comprises at least one selected from the group consisting of Al, Ag, and Cr. a metal element of Ni, Au, Qi, Fe, Zn, Sn, Mo or an alloy composed of the above-mentioned metal element.

The neutral gradation filter for a multilayer film layer according to claim 1, wherein the substrate is plated with at least two layers of the film layer.

The neutral gray-scale dimming filter of the multilayer film layer according to claim 1, 2 or 3, wherein the optical thickness of the film of the anti-reflection film ranges from 1 to 300 nm, The optical thickness of the film of the metal film ranges from 1 to 320 nm. .

The neutral gradation filter for a multilayer film according to claim 1, wherein the reflectance ranges from 1.50% to 2.30% in a wavelength range of 420 to 680 nm, and the transmittance is The range is 47.8%~51.3%.

The neutral gray-scale dimming filter of the multilayer film according to claim 1, wherein the reflectance of the maximum end of the attenuation is in the range of 2.5% to 3.1% in the wavelength range of 420 to 680 nm. range of transmittance was 11.45% ~12.06%, the range of the minimum reflectance end attenuation of 1.5% to 2.3%, a transmittance in the range of 47.8% -96.3% ₀

The apparatus for manufacturing a neutral gray scale filter of a multilayer film according to claim 1, comprising: a vacuum chamber, a coated umbrella and a power source, wherein the coated umbrella is fixed in a cavity of the vacuum chamber At the top of the body, the rotating shaft of the coated umbrella is connected to the power source, and is characterized by:

The bottom of the cavity of the vacuum chamber is provided with two symmetrically distributed sources of coated material, two of which are located under the coated umbrella; The correction plate is fixed in the vacuum chamber, and one end is located on the same side of the two coated materials.

The apparatus for manufacturing a neutral gray-scale dimming filter of a multilayer film according to claim 8, further comprising a baffle, wherein the baffle is provided with a plurality of symmetrically distributed gradient holes, The gradient hole has a blade shape in cross section.

The method of manufacturing a neutral gray-scale dimming filter for a multilayer film according to claim 1, comprising the steps of:

(1) placing the substrate in the vacuum chamber, pumping the vacuum chamber to a predetermined vacuum using a vacuum pump, and fixing the correction plate in the vacuum chamber;

(2) The power source drives the coating umbrella to rotate, and the two coating materials alternately vapor-deposit the film layer, and the film layers are sequentially laminated in a predetermined thickness and in a predetermined order.

The method of manufacturing a neutral gray scale filter of a multilayer film according to claim 10, wherein the correction plate in the step (1) is removed, in the step (1) and the step (2) The method further includes the step of installing the baffle under the film umbrella.