Light guide plate and virtual image display apparatus having the same
First Claim
1. A light guide plate comprising:
- a light incident part which takes image light to inside;
a light guide part which has first and second total reflection surfaces extending to face each other and guides the image light taken in from the light incident part by total reflection on the first and second total reflection surfaces;
an image extraction part which includes plural reflection units arrayed in a predetermined arraying direction and having a first reflection surface and a second reflection surface forming a predetermined angle with the first reflection surface, and which enables extraction of the image light to outside by bending an optical path in the reflection units so that the image light guided by the light guide part is reflected by the first reflection surface and the image light reflected by the first reflection surface is further reflected by the second reflection surface; and
a light exiting part having a light exiting surface which emits, to outside, the image light passed through the image extraction part;
wherein a space between the first and second reflection surfaces of the reflection units of the image extraction part and the light exiting surface is broader on the light incident part side than on a reflected light incident part side, andwherein the first reflection surface is perpendicular to the first total reflection surface, and the first reflection surface is perpendicular to the second total reflection surface.
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Accused Products
Abstract
Since a distance from an image extraction part to a light exiting surface is shorter downstream in an optical path than upstream in the optical path in relation to Z direction that is an arraying direction of reflection units, image light that propagates to pass between the image extraction part and the light exiting surface without becoming incident on the reflection units and therefore cannot be extracted to outside can be reduced. That is, since image light having a large total reflection angle in a light guide plate can be securely made incident on the image extraction part and efficiently extracted from the light exiting surface, light use efficiency in image formation can be enhanced. Thus, a virtual image display apparatus with brightness and high performance can be provided.
265 Citations
21 Claims
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1. A light guide plate comprising:
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a light incident part which takes image light to inside; a light guide part which has first and second total reflection surfaces extending to face each other and guides the image light taken in from the light incident part by total reflection on the first and second total reflection surfaces; an image extraction part which includes plural reflection units arrayed in a predetermined arraying direction and having a first reflection surface and a second reflection surface forming a predetermined angle with the first reflection surface, and which enables extraction of the image light to outside by bending an optical path in the reflection units so that the image light guided by the light guide part is reflected by the first reflection surface and the image light reflected by the first reflection surface is further reflected by the second reflection surface; and a light exiting part having a light exiting surface which emits, to outside, the image light passed through the image extraction part; wherein a space between the first and second reflection surfaces of the reflection units of the image extraction part and the light exiting surface is broader on the light incident part side than on a reflected light incident part side, and wherein the first reflection surface is perpendicular to the first total reflection surface, and the first reflection surface is perpendicular to the second total reflection surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
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Specification