Virtual image display device and optical unit
A virtual image display device includes a display panel being a display element configured to emit image light, a light-guiding member including a first total reflection surface and a second total reflection surface, a first diffraction element being provided on a light incidence side in association with the light-guiding member, a second diffraction element being provided on a light emission side in association with the light-guiding member, and a stray light suppression filter being provided on an external side of an image extraction part provided with the second diffraction element and being configured to limit passage of diffracted light from the second diffraction element.
1 . A virtual image display device, comprising:
a display element configured to emit image light;
a light-guiding member including a first total reflection surface and a second total reflection surface;
a first diffraction element being provided on a light incidence side in association with the light-guiding member;
a second diffraction element being provided on a light emission side in association with the light-guiding member; and
a stray light suppression filter being provided on an external side of an image extraction part provided with the second diffraction element and being configured to limit passage of diffracted light from the second diffraction element.
2 . The virtual image display device according to claim 1 , wherein
the stray light suppression filter is an angle-limiting filter including a light shielding part arranged repeatedly at a predetermined interval in a flat plate.
3 . The virtual image display device according to claim 1 , comprising
a filter configured to limit passage of diffracted light having a specific wavelength, among diffracted light having a plurality of wavelengths from the second diffraction element.
4 . The virtual image display device according to claim 1 , wherein
the stray light suppression filter includes a plurality of filters configured to limit passage of diffracted light of a plurality of orders from the second diffraction element.
5 . The virtual image display device according to claim 1 , comprising
a light transmission member having a flat plate shape and being arranged on the external side of the image extraction part, wherein
the stray light suppression filter is provided on any one of an external side or an eye position side of the light transmission member.
6 . The virtual image display device according to claim 5 , wherein
the light transmission member is made of a resin, and
the light-guiding member is made of glass.
7 . The virtual image display device according to claim 5 , wherein
the stray light suppression filter is provided on each of the external side and the eye position side of the light transmission member.
8 . The virtual image display device according to claim 1 , wherein
the first diffraction element and the second diffraction element diffract image light having a plurality of wavelengths separately.
9 . The virtual image display device according to claim 1 , comprising:
a third diffraction element being interposed between the first diffraction element and the second diffraction element and being configured to guide image light in a direction intersecting with a diffraction direction of the first diffraction element.
10 . The virtual image display device according to claim 1 , comprising:
a wavelength-limiting filter being arranged in an optical path from the display element to a light emission side of the second diffraction element and being configured to prevent emission of the diffracted light to an external side of the second diffraction element.
11 . The virtual image display device according to claim 1 , wherein
the stray light suppression filter is a wavelength-limiting filter that prevents emission of the image light to the external side of the second diffraction element.
12 . An optical unit, comprising:
a display element configured to emit image light;
a light-guiding member including a first total reflection surface and a second total reflection surface;
a first diffraction element being provided on a light incidence side in association with the light-guiding member;
a second diffraction element being provided on a light emission side in association with the light-guiding member; and
a stray light suppression filter being provided on an external side of an image extraction part provided with the second diffraction element and being configured to limit passage of diffracted light from the second diffraction element.