Display apparatus and display unit

Abstract

A display apparatus of the present technique includes for use with a light transmissive display member and is configured to project an image onto the light transmissive display member to forms a virtual image of the image, on an opposite side of the display member from a user. The display apparatus includes a display device housed in a housing and configured to display an image, and a projection optical system housed in the housing and configured to project the image displayed on the display device onto the display member. The housing has an opening through which projection light is emitted. The projection optical system includes, on an optical path from the display device to the opening, a first reflection member disposed on a display device side, and a second reflection member disposed on the opening side.

What is claimed is: 
     
         1 . A display apparatus for use with a light transmissive display member and configured to project an image onto the light transmissive display member to form a virtual image of the image, on an opposite side of the display member from a user, the display apparatus comprising;
 a display device housed in a housing and configured to display an image; and   a projection optical system housed in the housing and configured to project the image displayed on the display device onto the display member,   wherein   a housing having an opening through which projection light is emitted;   the projection optical system includes, on an optical path from the display device to the opening, a first reflection member disposed on a display device side, and a second reflection member disposed on an opening side,   the second reflection member has a reflection surface which projects the image onto the display member and has a free curved concave shape, and   a relationship between a vertical length Yv of the image displayed on the display device and a distance T, on a central optical path, from the user to the virtual image satisfies 0.03<√(T×Lv)/Yv<0.22, where Lv is a vertical length of the virtual image of the image.   
     
     
         2 . The display apparatus according to  claim 1 , wherein, in the display apparatus, a distance D 12  between the first reflection member and the second reflection member and a distance DL 1  between the first reflection member and the image on the display device satisfy 3.0<D 12 /DL 1 . 
     
     
         3 . The display apparatus according to  claim 1 , wherein the reflection surface of the first reflection member has a rotationally asymmetric convex shape. 
     
     
         4 . A display apparatus for use with a light transemissive display member and configured to project an image onto the light transmissive display member to form a virtual image of the image on an opposite side of the display member from a user, the display apparatus comprising:
 a display device configured to display an image; and   a projection optical system configured to project the image displayed on the display device onto the display member,   wherein   the projection optical system includes, on an optical path from the display device to the display member, a first reflection member disposed on a display device side, and a second reflection member disposed on a display member side,   the second reflection member has a reflection surface which projects the image onto the display member and has a free curved concave shape, and   a relationship between a vertical length Yv of the image displayed on the display device and a distance T, on a central optical path, from the user to the virtual image satisfies 0.03<√(T×Lv)/Yv<0.22, where Lv is a vertical length of the virtual image of the image.   
     
     
         5 . The display apparatus according to  claim 4 , wherein a distance D 12  between the first reflection member and the second reflection member and a distance DL 1  between the first reflection member and the image on the display device satisfy 3.0<D 12 /DL 1 . 
     
     
         6 . The display apparatus according to  claim 4 , wherein the reflection surface of the first reflection member has a rotationally asymmetric convex shape.