Display apparatus, moving body and light source apparatus having a light source, liquid-crystal panel, beam splitter, and light guiding member
A liquid crystal panel includes a first transmissive member having a first face where light enters, a liquid crystal layer, and a second transmissive member having a second face where at least a part of light having passed through the first transmissive member and the liquid crystal layer exits. The second face is inclined relative to the liquid crystal layer.
1. A light source apparatus, comprising:
a light source element configured to emit light;
a liquid crystal panel located in a progressive direction in a light path of light emitted from the light source element;
a beam splitter located in the progressive direction of the liquid crystal panel and is inclined relative to a plane vertical to the progressive direction; and
a light guiding member, wherein
the liquid crystal panel has a first face where light from the light source element enters and a second face where image projection light resulting from polarization of light having entered the first face in a predetermined polarization direction exits,
the beam splitter allows the image projection light having exited the second face of the liquid crystal panel and traveling in the progressive direction to pass through, and reflects external light traveling in a retrograde direction opposite to the progressive direction in a direction different from the progressive direction, and
the light guiding member is positioned to receive the external light reflected by the beam splitter and to emit the received external light into the liquid crystal panel by way of the first face of the liquid crystal panel.
2. The light source apparatus according to claim 1 , wherein the second face of the liquid crystal panel is inclined relative to a plane vertical to the progressive direction.
3. The light source apparatus according to claim 1 , wherein the beam splitter is a polarization beam splitter configured to allow light in the predetermined polarization direction to pass through.
4. The light source apparatus according to claim 1 , wherein the second face of the liquid crystal panel and the beam splitter are in contact with each other.
5. The light source apparatus according to claim 1 , wherein
the light guiding member includes:
an optical member configured to collect external light reflected by the beam splitter; and
an optical fiber having a first end where external light collected by the optical member enters and a second end where external light having entered the first end exits, and
external light having exited the second end of the optical fiber enters the first face of the liquid crystal panel.
6. The light source apparatus according to claim 5 , wherein
the light guiding member further has a diffusion member connected to the second end of the optical fiber, and
light having exited the second end of the optical fiber is diffused by the diffusion member and enters the first face of the liquid crystal panel.
7. The light source apparatus according to claim 1 , further comprising:
a first sensor configured to detect brightness of an image displayed on the liquid crystal panel; and
a controller configured to control a driving power of the light source element depending on a detection value of the first sensor.
8. The light source apparatus according to claim 1 , further comprising:
a second sensor configured to detect color temperature of external light entering the first face of the liquid crystal panel from the light guiding member; and
a controller configured to adjust color of the light source element depending on a detection value of the second sensor.
9. A display apparatus configured to allow a user to visually recognize a virtual image of an image, comprising:
a light source element configured to emit light;
a liquid crystal panel located in a progressive direction in a light path of light emitted from the light source element;
a beam splitter located in the progressive direction of the liquid crystal panel and is inclined relative to a plane vertical to the progressive direction;
one or more optical members; and
a light guiding member, wherein
the liquid crystal panel has a first face where light from the light source element enters and a second face where image projection light resulting from polarization of light having entered the first face in a predetermined polarization direction exits,
the beam splitter allows the image projection light having exited the second face of the liquid crystal panel and traveling in the progressive direction to pass through, and reflects external light traveling in a retrograde direction opposite to the progressive direction in a direction different from the progressive direction,
the one or more optical members allow the image projection light having passed through the beam splitter to reach a predetermined region in a real space, and
the light guiding member is positioned to receive the external light reflected by the beam splitter and to emit the received external light into the liquid crystal panel by way of the first face of the liquid crystal panel.
10. A moving body configured to allow a user to visually recognize a virtual image of an image, comprising:
a light source element configured to emit light;
a liquid crystal panel located in a progressive direction in a light path of light emitted from the light source element;
a beam splitter located in the progressive direction of the liquid crystal panel and is inclined relative to a plane vertical to the progressive direction;
one or more optical members; and
a light guiding member, wherein
the liquid crystal panel has a first face where light from the light source element enters and a second face where image projection light resulting from polarization of light having entered the first face in a predetermined polarization direction exits,
the beam splitter allows the image projection light having exited the second face of the liquid crystal panel and traveling in the progressive direction to pass through, and reflects external light traveling in a retrograde direction opposite to the progressive direction in a direction different from the progressive direction,
the one or more optical members allow the image projection light having passed through the beam splitter to reach a predetermined region in a real space, and
the light guiding member is positioned to receive the external light reflected by the beam splitter and to emit the received external light into the liquid crystal panel by way of the first face of the liquid crystal panel.
11. The moving body according to claim 10 , wherein
the moving body is a vehicle;
the one or more optical members include a windshield; and
the image projection light is reflected by the windshield and reaches the predetermined region in the real space.
12. The moving body according to claim 11 , wherein a polarizing filter is provided on a fourth face, which is different from a third face that reflects the image projection light, of the windshield, the polarizing filter being configured to attenuate or shield a component which is in a same polarization direction as the image projection light out of light entering.