A lens enhancement sheet convenient for repair and preparation method thereof

Abstract

The present invention relates to an enhanced lens that is easy to repair and a preparation method thereof, comprising a lens substrate, a silver layer with a thickness of 2 to 4 nm plated on the outer side of the lens substrate, and an anti-reflection film layer plated on the outer side of the silver layer. The lens substrate is glass with a refractive index range of 1.46-2.1 or a crystal with a refractive index range of 1.38-2.4. The anti-reflection film layer comprises a first H4 film layer with a thickness of 25.1-28.7 nm, a first MgF2 film layer with a thickness of 35.4-33.2 nm, a second H4 film layer with a thickness of 130.4-139.0 nm, and a second MgF2 film layer with a thickness of 87.1-92.2 nm, which are stacked in sequence from the inside to the outside. The reflective enhancement lens uses ultra-thin AG as the transition layer between the substrate and the anti-reflection film AR film layer. The ultra-thin AG layer has low refractive index and low absorption characteristics in the visible light band, which will not weaken the anti-reflection effect of the anti-reflection film. In addition, the AG layer can be removed by chemical immersion when there is a problem with the coating quality, which has the effect of completely stripping off the AR film, and then the anti-reflection film can be re-deposited. This can increase the repair rate of the reflective enhancement lens, reduce production costs, and make outstanding contributions to industrial applications.

Description

Technical Field

[0001] The invention relates to the field of optics, and in particular to a lens enhancement sheet which is easy to repair and a preparation method thereof. Background Art

[0002] When light is incident vertically on an ordinary glass surface, the ratio of the intensity of the reflected light on the incident surface to the intensity of the incident light (reflectivity) is only determined by the ratio of the refractive indices of the adjacent media: the reflection of each surface of crown glass with a refractive index of 1.52 is about 4.2%. The surface reflection of flint glass with a higher refractive index is more significant. This surface reflection has two serious consequences: the loss of light energy reduces the brightness of the image; the surface reflected light is reflected or diffused many times, and part of it becomes stray light, which finally reaches the image plane and reduces the contrast of the image and the image quality. In particular, complex systems such as television and movie camera lenses contain many surfaces adjacent to the air. If they are not coated with an anti-reflection film, their performance will be greatly reduced. Therefore, these instruments must be coated with an anti-reflection film on the surface.

[0003] There are many optical instruments used in the visible spectrum region, which account for the vast majority of anti-reflection coatings in terms of output. Anti-reflection treatment is required on almost all optical devices. In particular, the surface of visible vision optical lenses is generally coated with visible width anti-reflection coating to increase the light transmission of the lens and reduce image quality problems such as ghosting.

[0004] The coating process usually uses PVD (physical vapor deposition) technology. Although the coating equipment and process technology are mature now, the control accuracy of the film thickness is at the nanometer level. In addition to the spectral reflectivity index requirements, the anti-reflection film also has performance requirements such as smoothness and firmness. Therefore, if the coating index or other performance indicators are unqualified, the lens can only be scrapped, because it is very difficult to completely remove the film layer deposited on the surface of the lens. The film layer cannot be removed completely by chemical methods. The residual uneven film layer will affect the film color and cause abnormalities such as color spots. The physical re-polishing method will cause the lens to have unqualified sagittal height due to excessive removal of the lens substrate. The rework cost is high and the yield rate is low. Summary of the invention

[0005] The present invention provides a lens enhancement sheet that is easy to repair and a preparation method thereof. The lens enhancement sheet that is easy to repair can remove the film layer coated on the lens if the coating index or other performance index is unqualified, and the anti-reflection effect will not be weakened after the coating is successful, so that the lens enhancement sheet has excellent anti-reflection effect in the visible light range.

[0006] The present invention is achieved through the following technical solutions:

[0007] A lens enhancement film convenient for repair comprises a lens substrate, a silver layer with a thickness of 2 to 4 nm plated on the outer side of the lens substrate, and an anti-reflection film layer plated on the outer side of the silver layer.

[0008] Preferably, the lens substrate is glass with a refractive index ranging from 1.46 to 2.1 or a crystal with a refractive index ranging from 1.38 to 2.4.

[0009] Preferably, the antireflection film layer includes a first H4 film layer with a thickness of 25.1-28.7 nm, a first MgF2 film layer with a thickness of 35.4-33.2 nm, a second H4 film layer with a thickness of 130.4-139.0 nm, and a second MgF2 film layer with a thickness of 87.1-92.2 nm, which are stacked in sequence from the inside to the outside.

[0010] A method for preparing an enhanced lens that is easy to repair includes the following steps: first cleaning the lens substrate, then plating a 2-4nm silver layer on the outer side of the lens substrate, and finally plating the anti-reflection film layer on the outer side of the silver layer.

[0011] Compared with the prior art, the present invention has the following beneficial effects: the lens enhancement sheet of the present invention adopts ultra-thin AG as a transition layer between the substrate and the anti-reflection film AR film layer. The ultra-thin layer AG has low refractive index and low absorption characteristics in the visible light band, which will not weaken the anti-reflection effect of the anti-reflection film. Moreover, the AG layer can be removed by chemical immersion method after the coating quality problem occurs, that is, the AR film can be completely stripped off, and then the anti-reflection film can be re-deposited. Therefore, the repair rate of the lens enhancement sheet can be improved, thereby reducing the production cost, which has an outstanding contribution to industrial applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural diagram of embodiment 1 of the present invention.

[0013] Figure 2 It is a reflectance spectrum diagram within the wavelength range of 380-780nm of Example 1 of the present invention.

[0014] Figure 3 It is a reflectance spectrum diagram within the wavelength range of 380-780nm of Example 2 of the present invention.

[0015] Figure 4 It is a reflectance spectrum diagram within the wavelength range of 380-780nm of Example 3 of the present invention.

[0016] Figure 5 It is a reflectance spectrum diagram of Example 4 of the present invention within the wavelength range of 380-780nm.

[0017] Figure 6It is a reflectance spectrum diagram within the wavelength range of 380-780nm of Example 5 of the present invention.

[0018] Figure 7 It is a reflectance spectrum diagram of Example 6 of the present invention within the wavelength range of 380-780nm. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with specific embodiments:

[0020] Example 1

[0021] like Figure 1 As shown, a lens enhancement lens that is easy to repair includes a lens substrate 1, a silver layer 2 with a thickness of 2 to 4 nm plated on the outer side of the lens substrate 1, and an anti-reflection film layer 3 plated on the outer side of the silver layer 2.

[0022] The lens substrate 1 described in this embodiment is K9 glass N=1.52.

[0023] The antireflection film layer 3 includes a first H4 film layer 3-1 with a thickness of 27.9 nm, a first MgF2 film layer 3-2 with a thickness of 32.2 nm, a second H4 film layer 3-3 with a thickness of 135.0 nm, and a second MgF2 film layer 3-4 with a thickness of 89.5 nm, which are stacked in sequence from the inside to the outside.

[0024] Example 2

[0025] Different from the above-mentioned embodiment 1, the anti-reflection film layer 3 described in this embodiment includes a first H4 film layer 3-1 with a thickness of 27.1nm, a first MgF2 film layer 3-2 with a thickness of 31.2nm, a second H4 film layer 3-3 with a thickness of 131.0.0nm and a second MgF2 film layer 3-4 with a thickness of 86.8nm, which are stacked in sequence from the inside to the outside.

[0026] Example 3

[0027] Different from the above-mentioned embodiment 1, the anti-reflection film layer 3 described in this embodiment includes a first H4 film layer 3-1 with a thickness of 28.7nm, a first MgF2 film layer 3-2 with a thickness of 33.2nm, a second H4 film layer 3-3 with a thickness of 139.0nm and a second MgF2 film layer 3-4 with a thickness of 92.2nm, which are stacked in sequence from the inside to the outside.

[0028] Example 4

[0029] The lens substrate 1 described in this embodiment is a quartz crystal N=1.55

[0030] The antireflection film layer 3 includes a first H4 film layer 3-1 with a thickness of 25.9 nm, a first MgF2 film layer 3-2 with a thickness of 36.5 nm, a second H4 film layer 3-3 with a thickness of 134.4 nm, and a second MgF2 film layer 3-4 with a thickness of 89.8 nm, which are stacked in sequence from the inside to the outside.

[0031] Example 5

[0032] Different from Example 4, the anti-reflection film layer 3 described in this embodiment includes a first H4 film layer 3-1 with a thickness of 25.1nm, a first MgF2 film layer 3-2 with a thickness of 35.4nm, a second H4 film layer 3-3 with a thickness of 130.4nm and a second MgF2 film layer 3-4 with a thickness of 87.1nm, which are stacked in sequence from the inside to the outside.

[0033] Example 6

[0034] Different from Example 4, the anti-reflection film layer 3 described in this embodiment includes a first H4 film layer 3-1 with a thickness of 26.7nm, a first MgF2 film layer 3-2 with a thickness of 37.6nm, a second H4 film layer 3-3 with a thickness of 138.4nm and a second MgF2 film layer 3-4 with a thickness of 92.5nm, which are stacked in sequence from the inside to the outside.

[0035] like Figure 2-7 As shown, Figure 2 The thin line in the middle represents the spectrum of the anti-reflection film without silver coating in the wavelength range of 380-780nm, and the thick line is the spectrum of the anti-reflection film with silver coating in the wavelength range of 380-780nm. It can be seen that the silver coating does not weaken the anti-reflection effect of the anti-reflection film in the wavelength range of 380-780nm. In practical applications, the chemical immersion method can be used to remove the AG layer after the coating quality problem occurs, that is, the AR film can be completely stripped off, and then the anti-reflection film can be re-deposited. Therefore, the repair rate of the anti-reflection lens can be improved, thereby reducing the production cost, which has an outstanding contribution to industrial applications.

[0036] The present invention is not limited to the above embodiments. Any improvement or replacement based on the principle of the present invention should be within the protection scope of the present invention.

Claims

1. A lens enhancement sheet that is easy to repair, characterized in that: The lens substrate (1) comprises a lens substrate (1), a silver layer (2) with a thickness of 2 to 4 nm plated on the outer side of the lens substrate (1), and an anti-reflection film layer (3) plated on the outer side of the silver layer (2); the lens substrate (1) is glass with a refractive index in the range of 1.46 to 2.1 or a crystal with a refractive index in the range of 1.38 to 2.

4.

2. The lens enhancement sheet that is easy to repair according to claim 1, characterized in that: The anti-reflection film layer (3) comprises a first H4 film layer (3-1) with a thickness of 25.1-28.7 nm, a first MgF2 film layer (3-2) with a thickness of 35.4-33.2 nm, a second H4 film layer (3-3) with a thickness of 130.4-139.0 nm, and a second MgF2 film layer (3-4) with a thickness of 87.1-92.2 nm, which are stacked in sequence from the inside to the outside.

3. A method for preparing a lens enhancement sheet that is easy to repair according to claim 1 or 2, characterized in that: First, the lens substrate (1) is cleaned, then a 2-4 nm silver layer (2) is plated on the outer surface of the lens substrate (1), and finally, the anti-reflection film layer (3) is plated on the outer side of the silver layer (2).

Images