JPS606905A - Polarizing film - Google Patents

Abstract

PURPOSE:To provide superior polarizing characteristics by forming silicon oxide layers on both sides or one side of a multilayered film formed by alternately laminating dielectric layers having a higher refractive index and dielectric layers having a lower refractive index so as to prevent the breakdown of the film due to the tensile stress of the different layers and to improve the moisture resistance. CONSTITUTION:An SiOx(1<x<=2) layer 34 is formed on a glass substrate 1, and dielectric layers 32 of ZnS or the like having a higher refractive index and dielectric layers 31 of cryolite or the like having a lower refractive index are alternately laminated on the layer 34 to form a multilayered dielectric film, e.g., a film consisting of seven layers. An SiOx layer 33 is then formed on the uppermost layer 32, and a glass substrate 2 is joined to the layer 33 with an adhesive 4 to obtain a polarizing film 3. By forming the SiOx films 33,34 on both sides of the film 3, the breakdown of the film 3 due to the tensile stress of the layers 31,32 is prevented, and the moisture resistance of the multilayered dielectric film is improved. The films 33,34 exert no unfavorable influence on the polarizing characteristics of the polarizing film.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polarizing film including a dielectric multilayer film for a polarizing prism.

In general, a polarizing prism having a polarizing film is made by attaching a polarizing film tightly between two 45° prism glass substrates 1 and 2 as shown in Figure 1, and adjusting the polarization of the incident light as shown in Figure 2. Separates waves and S waves.

Conventionally, this type of polarizing film has had a U4 structure as shown in FIG. That is, when the refractive index of the glass substrate 1.2 is approximately 1.6, magnesium fluoride (refractive index is approximately 1.3)
Below, a low refractive index M electric layer made of a material such as
It is called "1st layer". ) 31 and a high refractive index dielectric layer (hereinafter referred to as "layer 1") 32 made of a substance such as zirconium oxide (refractive index of approximately 2.04°). .

In this polarizing film, first, one layer 31 is deposited on the glass substrate 1 by a vacuum evaporation method or the like, and then layers 1-1 and 1-1 layers 31 are alternately stacked one after another by a vacuum evaporation method or the like. 13 layers were formed. After that, the polarizing film laminated on the ζ glass substrate 1'' is cleaned, and an adhesive 4 such as optical bond is applied.
was bonded to the other glass substrate 2. Furthermore, in other conventional polarizing films, the glass substrates 1 and 2 have a refractive index of about 1.55, one layer 31 is made of cryolite (refractive index is about 1.25 degrees), and the H layer 32 is made of sulfurized material (refractive index of about 1.25 degrees). Refractive index is approximately 2.2
9 o), and were formed by alternately laminating them in the same manner as above.

However, in the polarizing film of the conventional dielectric multilayer film, when the H layer and the L layer are made of a material having tensile stress (for example, the 1-1 layer is zirconium oxide, and the L layer is magnesium fluoride), the polarizing film When the number of dielectric layers that form a large number of layers increases, there is a drawback that the device breaks down due to tensile stress. In order to prevent this, it is possible to reduce the thickness of layer 1 and increase the thickness of the FI layer, but the polarization properties deteriorate, so it is necessary to further increase the thickness of the FI layer to obtain the desired polarization properties. Although the number of L layers such as "1" layer is increased, the same disadvantage as described above is that it breaks due to tensile stress. Furthermore, the polarizing film using zinc sulfide and cryolite not only has the above-mentioned drawbacks, but also has the drawback that it is sensitive to moisture and must be cleaned under strict conditions in the process of cleaning the polarizing film.

The present invention has been made in order to eliminate the above-mentioned drawbacks of the conventional technology, and provides a polarizing film in which a layer of silicon oxide is attached to a dielectric multilayer film. The purpose is to prevent destruction. Another object of the present invention is to improve moisture resistance, and a further object is to peel off the dielectric multilayer film from the glass substrate by attaching a silicon oxide layer to the glass substrate and the dielectric multilayer film. The goal is to prevent this from happening.

Hereinafter, the present invention will be explained in detail based on the drawings.

(Example 1) This will be explained based on FIG. 4. 3 is a dielectric multilayer film made by alternately laminating 11 layers 32 and 1 layer 31 (described later), and the layers at both ends of the dielectric multilayer film are 11 layers 32.
The layers 1-: layer 32 at both ends are polarizing films to which 8102 layers 33 and 34, which will be described later, are attached, 31 is the L layer of cryolite, 32 is the 1-1 layer of zinc sulfide, and 33
is attached to the main surface of the dielectric multilayer film, and the five layers 02 and 34 are adhered to the adhesive 4 such as optical bond, and the layer 34 is attached to the other main surface of the dielectric multilayer film. There are 5102 layers attached to the glass substrate 1. In order to interpose this embodiment between the glass substrates forming the polarizing prism, first the SiO2 layer 34 is deposited on the glass substrate 1 to a thickness of about 1530 mm, and then the 8102 layer 34
Deposit the 1-1 layer 32 on top to a thickness of about 750 nm, then deposit the 1-1 layer 31 on the 11 layer 32 to a thickness of about 2500 nm, then apply the The H layer 32 and the above layer 31 are laminated alternately to increase the number of layers of the dielectric multilayer film to 7.
Approximately 1,530 of the 5 layers 02 and 33 are deposited on the final H layer 32 constituting the dielectric multilayer film, and then,
The polarizing film 3 attached to the glass substrate 1 is washed and dried, and then the polarizing film 3 is bonded to the other glass substrate 2 using an adhesive 4. 8102 layer 33, 34.1-
Layer 1 32. Layer 1 31 is deposited by vacuum evaporation or the like. The spectral reflectance curve for the polarizing prism formed as described above is shown in FIG. 6A. For reference, FIG. 6B shows a spectral reflectance curve for a polarizing prism having a conventional polarizing film to which the SiO2 layers 33 and 34 are not attached.

Comparing the spectral reflectance curves △ and B, there is no significant difference in polarization characteristics, and there is no effect of attaching the 5-layer 02 layer to both sides of the dielectric multilayer film. According to this example, destruction of the dielectric multilayer film could be prevented without impairing the polarization characteristics. Furthermore, since the SiO2 layer is attached to the glass substrate and the M electric multilayer film, it is possible to prevent the dielectric multilayer film from peeling off from the glass substrate.
Since the SiO2 layer is attached to the adhesive and the dielectric multilayer film, the moisture resistance of the dielectric multilayer film is also improved.

(Example 2) This will be explained based on FIG. 5. 3 forms a dielectric multilayer film by alternately laminating 1 layers 31 and 11 layers 32 (to be described later), and between both ends of the M electric multilayer film, the layer attached to the glass substrate 1 is 1 layer 31. The layer attached to the 8102 layer 33 (described later) on the glass substrate 2 side is H
A polarizing film forming a layer 32, 31 is lJi of magnesium fluoride, 32 is a [-1 layer of zirconium oxide, 33 is attached to the entire surface of the dielectric multilayer film, and an adhesive 4 such as an optical bond is attached. There are 5 layers and 02 layers adhered to. The thicknesses of the above layer 31, H layer 32, and 5-layer 02 layer 33 are about 1900, about 900, and about 1600, respectively.

The method of interposing this embodiment between the glass substrates forming the polarizing prism is the same as that of the first embodiment. According to this example, as in the previous example, destruction of the dielectric multilayer film can be prevented, and since the SiO2 layer is attached to the adhesive and the dielectric multilayer film, moisture resistance is improved. Cleaning strip f]
was also eased.

Second, in Examples 1 and 2, the SiO2 layer was used as the silicon oxide layer, but the silicon oxide layer is not limited to this, and any SiOx layer (1<x≦2) can be used in the same manner as the SiO2 layer. , having compressive stress has the effect of preventing damage to the dielectric multilayer film.

Next, in Examples 1 and 2, the 171 layer uses zinc sulfide or zirconium oxide, and the L layer uses Cryolite I.
・Or, although magnesium fluoride is used, the material is not limited to these materials, and dielectric materials having a relatively high refractive index and a dielectric material having a low refractive index may be used in 1-1 layers and the L layer, respectively. Bye. For example, the 1-1 layer is relium oxide, titanium dioxide, tantalum oxide, lead fluoride, magnesium oxide, yttrium oxide, etc., and the L layer is calcium fluoride, etc.
You can use Chi Δ Light etc. Next, silicon oxide layer Si
The thickness of the Ox layer (SiO2 layer in Examples 1 and 2) is such that when the refractive index difference between the glass substrate and the 3iQx layer is very large, if the thickness of the 5IOx layer is large, the P wave The optical thickness of the 5iOX layer must be 5λ/2 in order to maintain good polarization properties, since the spectral polarization rate changes little by little as the wavelength changes. 4(λ:
Wavelength of incident light. ) The following is desirable. Next, the number of layers constituting the dielectric multilayer film may be as long as it has the desired polarization characteristics as a polarizing prism.

Next, in Example 2, the 1-1 layer is injected into the SiO2 layer.
However, the L layer may be attached to the SiO2 layer. That is, in Example 2, the 1-1 layer is the L layer, and the L layer is
The layer may be replaced with a 1'' layer. Furthermore, even if the 3iQx layer is formed between the glass substrate 1 and the dielectric multilayer film, and is not formed between the adhesive and the dielectric multilayer film, it is possible to prevent damage to the dielectric multilayer film 1 and prevent the dielectric multilayer film from being destroyed. peeling can be prevented.

As described above, according to the present invention, by attaching the SiOx layer to the dielectric multilayer film, it is possible to prevent the dielectric multilayer film from breaking by 1 m without significantly impairing the polarization properties, and to improve moisture resistance.
This was effective in preventing peeling of the dielectric multilayer film from the glass substrate.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a general polarizing prism, Fig. 2 is a schematic diagram showing the relationship between the plan view of Fig. 1 and incident light, P waves, and S waves, and Fig. 3 is a diagram of a conventional polarizing film. 4 is a sectional view of one embodiment of the present invention, FIG. 5 is a sectional diagram of another embodiment of the present invention, and FIG. 6 is a wavelength and P wave according to the embodiment of FIG.
The figure which shows the relationship of spectral reflectance with S wave. 1.2...Glass substrate, 3...Polarizing film, 4...Adhesive, 31...Shipping layer, 32...11 layer, 33°34
...5102 layers

Claims (1)

[Claims] (1) A 5iOx (1 < A polarizing film characterized by: (2. In claim 1, each layer of a plurality of dielectric material layers having a high refractive index constituting the dielectric multilayer film is made of substantially the same material, and the dielectric multilayer film is 1. A polarizing film, wherein each of the plurality of dielectric material layers having a low refractive index is made of substantially the same material.