Optical system, optical member, micromirror array, display device, and image-capturing device

Abstract

An optical system includes: a first optical member having a concave surface that reflects a light having a first circularly polarized light component and transmits a light having a second circularly polarized light component a rotation direction of which is opposite to a rotation direction of the first circularly polarized light component; and a second optical member that transforms the light having the first circularly polarized light component reflected from the first optical member into the light having the second circularly polarized light component to be reflected so as to be incident on the first optical member.

1 . An optical system, comprising:
 a first optical member that transforms a first polarized light into a second polarized light;   a second optical member having a plurality of concave surfaces that reflects the second polarized light having been transformed by the first optical member to be incident on the first optical member, wherein:
 the first optical member transforms the second polarized light having been reflected by the plurality of concave surfaces of the second optical member into a third polarized light and reflects the third polarized light to be incident on the second optical member; and 
 the plurality of concave surfaces of the second optical member transmit the third polarized light having been reflected by the first optical member. 
   
     
     
         2 . The optical system according to  claim 1 , wherein:
 the first optical member includes a third optical member and a fourth optical member;   the third optical member transforms the first polarized light into the second polarized light to be incident on the second optical member, transforms the second polarized light having been reflected by the plurality of concave surfaces of the second optical member into a fourth polarized light to be incident on the fourth optical member, and transforms the fourth polarized light having been reflected by the fourth optical member into the third polarized light to be incident on the second optical member; and   the fourth optical member transmits the first polarized light to be incident on the third optical member, and reflects the fourth polarized light having been transformed by the third optical member to be incident on the third optical member.   
     
     
         3 . The optical system according to  claim 2 , wherein:
 the third optical member includes a wave plate; and   the fourth optical member includes a polarizer plate.   
     
     
         4 . The optical system according to  claim 1 , wherein:
 the plurality of concave surfaces of the second optical member orient to the first optical member.   
     
     
         5 . The optical system according to  claim 1 , wherein:
 the first optical member includes a fifth optical member that is capable of transforming a polarized light;   the first optical member switches between a state in which the first polarized light is transformed into the second polarized light to be incident on the second optical member and a state in which the first polarized light is transformed into the third polarized light to be incident on the second optical member, by making the fifth optical member transform a polarized light or not.   
     
     
         6 . The optical system according to  claim 5 , wherein:
 the first optical member further includes a third optical member and a fourth optical member;   the fifth optical member is provided between the third optical member and the fourth optical member; and   the fifth optical member switches between a state in which the first polarized light having transmitted through the fourth optical member is not transformed and is transformed into the second polarized light by the third optical member to be incident on the second optical member, and a state in which the first polarized light having transmitted through the fourth optical member is transformed into the fourth polarized light and the fourth polarized light having been transformed is transformed into the second polarized light by the third optical member to be incident on the second optical member.   
     
     
         7 . The optical system according to  claim 6 , wherein:
 the fifth optical member includes a liquid crystal plate; and   a state in which a polarized light is transformed and a state in which a polarized light is not transformed are switched by an applied voltage to the liquid crystal plate.   
     
     
         8 . The optical system according to  claim 1 , wherein:
 there is provided a member that reflects the second polarized light and transmits the third polarized light at the plurality of concave surfaces of the second optical member.   
     
     
         9 . The optical system according to  claim 8 , wherein:
 the member that reflects the second polarized light and transmits the third polarized light includes a liquid crystal.   
     
     
         10 . The optical system according to  claim 1 , wherein:
 the first polarized light corresponds to a first linearly polarized light;   the second polarized light corresponds to a first circularly polarized light;   the third polarized light corresponds to a second circularly polarized light; and   the fourth polarized light corresponds to a second linearly polarized light.   
     
     
         11 . The optical system according to  claim 10 , wherein:
 the first circularly polarized light has a polarization direction that is opposite to a polarization direction of the second circularly polarized light; and   the first linearly polarized light has a polarization direction that is orthogonal to a polarization direction of the second linearly polarized light.   
     
     
         12 . The optical system according to  claim 11 , wherein:
 the first circularly polarized light corresponds to a right circularly polarized light;   the second circularly polarized light corresponds to a left circularly polarized light;   the first linearly polarized light corresponds to a P-polarized light; and   the second linearly polarized light corresponds to a S-polarized light.   
     
     
         13 . The optical system according to  claim 1 , further comprising:
 a sixth optical member, wherein:
 the sixth optical member transforms a circularly polarized light, which is incident on the second optical member via the sixth optical member and is reflected, into a linearly polarized light, and shields the linearly polarized light having been transformed. 
   
     
     
         14 . The optical system according to  claim 13 , wherein:
 the sixth optical member includes a polarizer plate and a wave plate;   the polarizer plate absorbs the first linearly polarized light and transmits the second linearly polarized light to be incident on the wave plate;   the wave plate transforms the second linearly polarized light having transmitted through the polarizer plate into a first circularly polarized light to be incident on the second optical member, and transforms the first circularly polarized light having been reflected at the plurality of concave surfaces of the second optical member into the first linearly polarized light to be incident on the polarized plate.   
     
     
         15 . The optical system according to  claim 1 , wherein:
 the first polarized light is transformed into the second polarized light by the first optical member to be incident on the second optical member;   the second polarized light having been transformed by the first optical member is reflected by the plurality of concave surfaces of the second optical member to be incident on the first optical member;   the second polarized light having been reflected by the plurality of concave surfaces of the second optical member is transformed into the third polarized light by the first optical member into the third polarized light and is reflected to be incident on the second optical member; and   the third polarized light transmits through the plurality of concave surfaces of the second optical member.