JPS6015255B2 - Polarization separation light control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polarization separation light control device, particularly a polarization separation light control device that separates a P-wave component and an S-wave component, controls each component, and synthesizes each component. This invention relates to a polarization separation light control device that uses a light polarization filter made up of a plurality of types of dielectric thin films, separates the light through the light polarization filter, and then combines the light through a light control means. .

BACKGROUND ART A polarizer using a back-refractive optical crystal such as calcite or rutile has been well known as a means for separating polarized components of light. However, these are expensive, and when turning them into prisms, it is necessary to align the optical axes, which is a difficult task as well as ensuring correct prism angle accuracy, which also causes the high cost. On the other hand, an optical polarizing filter as described later with reference to FIG.
It is known to have the property of easily reflecting wave components. However, in the past, only one of the P-wave component or the S-wave component separated by the outside of the polarizing filter was used, and the other was discarded.
The present invention improves the above-mentioned points by controlling the P-wave component and the S-wave component separated by the outside of the polarizing filter by a light control means, and then combining them again. The separated P while passing through
The above-mentioned synthesis can be easily performed by making sure that the wave component and the S-wave component proceed in parallel with each other.

The object of the present invention is to provide a polarization separation light control device.
To this end, the polarization separation light control device of the present invention separates light containing a P-wave component and an S-wave component into a P-wave component and an S-wave component, and then controls each component. In the polarization separation light control device that synthesizes the polarization, a dielectric multilayer film in which multiple types of dielectric thin films are laminated in a multilayer structure is used as an optical polarization filter, and the P wave component and the S wave component are individually controlled. the P-wave component and the S-wave component are separated by the interposition of the polarizing filter, and one of the separated P-wave component and S-wave component is reflected by total internal reflection or by using a crab body multilayer film, so that they are parallel to each other. The light control means is interposed for the separated P wave component and S wave component that have started to travel in the same direction, and the P wave component and S wave component that have passed through the light control means are It is characterized in that it is constructed so that the wave components are synthesized using similar total reflection or a dielectric multilayer layer and a light polarizing filter. This will be explained below with reference to the drawings. FIG. 1 is an explanatory diagram for explaining the optical polarizing filter according to the present invention, FIG. 2 is an explanatory diagram for explaining the operation of an optical interference polarizer using the optical polarizing filter, and FIG. 3 is an embodiment of the present invention. shows. In FIG. 1, 1 is a light polarizing filter, 2
-1, 2-2, 2-3, 2-4, . . . represent dielectric layers, respectively.

For example, dielectric layers 2-1, 2-2,...
. . . has a relationship such that the dielectric constant is large 4 and large small, and has a layer thickness of ^/4 with respect to the wavelength of light. As is well known, when considering the wavelength of light, the reflectance of such a polarizing filter 1 rapidly decreases below a predetermined wavelength. In the vicinity, the reflectance of the P wave component and the reflectance of the S wave component are relatively significantly different.
Furthermore, if the angle of incidence of light incident on the polarizing filter is taken as a horizontal mirror, the reflectance of the S-wave component increases monotonically as the angle of incidence increases, while the reflectance of the P-wave component increases as the angle of incidence increases. has a minimum value when it is near a predetermined angle. FIG. 2 explains the operation of the optical interference polarizer based on the outside of the optical polarizing filter.

The code 1 in the figure corresponds to FIG. 1, 3 is an optical interference polarizer, and 4 is an optical interference polarizer.
is the atmosphere, 5 and 6 are glass, for example, and have a refractive index equal to or larger than 4 mm of the refractive index of the material used for the polarizing filter, 7 is the input light,
8 represents the reflected S-wave component, and 9 represents the transmitted P-wave component. When input light 7 containing a P-wave component and an S-wave component is input to the polarizing filter 1 through the glass 5 at a predetermined angle of incidence, the S-wave component included in the input light 7 is as shown in the figure. The P wave component contained in the input light 7 is reflected as the S wave component 8 and transmitted as the P wave component 9 shown.

FIG. 3 shows an embodiment of the present invention, and FIGS. 3A and 3B show different operating modes.

Symbols IA and IB in the figure are optical polarizing filters corresponding to those in FIG. 2, 3A and 3B are optical interference polarizers, and 5A and 58 and SA and 6B are glasses, respectively, corresponding to FIG. 2. 7, 8 and 9 correspond to those shown in FIG. 2, 10 and 11 are input lights to the polarizer 3B', 12 and 12' are output lights, respectively, 13A and 138 are total reflection surfaces, and 14 represents a light control means. In a mode (temporarily referred to as on mode) in which the light inputted from the left side in the figure is outputted by the light control means 14 at 90°, the polarizer 3A converts the S-wave component 8 into and P wave component 9
The light control means 14 performs the above-mentioned light control (addition of other controls other than light control is optional), and the light polarization filter IB on the polarizer 3B The output light 12 is synthesized.

That is, the S-wave component 8 separated by the optical polarization filter IA as described with reference to FIG. 2 is supplied to the light control means 14 via the total reflection surface 13A. And as shown in the diagram 9
The input light 10 is a P-wave component subjected to 0o light, and is transmitted through the optical polarization filter IB to become output light 12. Further, the separated P wave component 9 passes through the light control means 14 and is subjected to 90° beaming to become the input light 11 of the S wave component, which becomes the polarizer 3B and is reflected by the optical polarization filter IB to become the output light 12. Become. In the case shown in FIG. 3B, the light control means 14 is in an OFF mode and does not emit light.

In this case, the illustrated input light 10 remains an S-wave component, and the input light 11 remains a P-wave component. For this purpose, the input light 10 of the S wave component is reflected on the optical polarization filter IB, and the P
The wave component input light 11 is transmitted through the optical polarization filter IB,
This becomes output light 12'. That is, depending on whether the light control means 14 is turned on or off, the output direction of the output lights 12, 12' is switched. Note that the P-wave component and the S-wave component passing through the light control means travel parallel to each other, and since they each travel parallel to each other within the light control means, there is no risk of characteristic deterioration. As explained above, according to the present invention, the P-wave component and/or S-wave component separated using an optical polarization filter can be controlled by the light control means and then combined again.

Further, although specific explanation has been omitted in the explanation related to FIG. 3, the optical path of the bridge wave component can be switched or made irreversible. This makes it possible to construct optical switches, optical circulators, and the like.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is an explanatory diagram for explaining the optical polarizing filter according to the present invention, Fig. 2 is an explanatory diagram for explaining the operation of the optical polarizer due to the outside of the optical polarizing filter, Figure 3 shows an embodiment of the invention. In the figure, 1 is a polarizing filter, 2-1, 2-2,...
・・・・・・・・・ is the mysterious turtle layer, 3 is the optical interference polarizer, 4
is the atmosphere, 5 and 6 are glass respectively, 13 is the total reflection surface, 14
represents a light control means. Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] 1 In a polarization separation light control device that separates light containing a P-wave component and an S-wave component into a P-wave component and an S-wave component, controls each component, and synthesizes each component, there are multiple types of polarization separation light control devices. A dielectric multilayer film obtained by laminating dielectric thin films of The separated P-wave component and the S-wave component are now propagated in parallel directions by total internal reflection or reflection of one of the separated P-wave component and S-wave component using a dielectric multilayer film. After interposing the above-mentioned light control means for the P-wave component and the S-wave component, respectively, the P-wave component and the S-wave component that have passed through the light control means are subjected to similar total reflection or dielectric multilayer film and optical polarization. A polarization separation light control device characterized in that it is configured to combine using a filter.