Optical system

An optical system comprising:

• a reflective imaging element;
• a liquid crystal display panel disposed on a light-incident side of the reflective imaging element, the liquid crystal display panel having a display surface which is inclined with an angle of no less than 15° and no more than 45° relative to a plane defined by the reflective imaging element, a viewing angle dependence of a contrast ratio of the liquid crystal display panel taking a central value in a normal direction of the display surface or in a direction inclined by more than 0° but less than 10° in a direction of tilt of the display surface from the normal direction;
• and
• a light guide element having an incident face, an outgoing face, and a plurality of light paths formed between the incident face and the outgoing face, the incident face being disposed on the reflective imaging element side of the display surface, and the outgoing face being inclined with an angle of no less than 45° and no more than 75° relative to the plane defined by the reflective imaging element, wherein
• the optical system causes an image displayed on the outgoing face of the light guide element to form an image at a position of planar symmetry with respect to the reflective imaging element as a plane of symmetry.