Patent ID: 11953681
Assignee: MAXELL, LTD.
Field: Optics (Instruments)
Classification: CPC G  B  H | IPC B  G

Claim 0:
1. A head up display for displaying a virtual image to a driver, the head up display comprising:
an image display device that includes a backlight and a liquid crystal panel;
a virtual image optical system that forms an optical path of an image light emitted from the liquid crystal panel; and
an outer housing that accommodates the image display device and the virtual image optical system, wherein
the outer housing includes:
an outer case, to which the image display device is to be mounted, that accommodates the virtual image optical system;
an upper cover that covers an upper portion, through which the image light is emitted, of the outer case;
a bottom cover that covers a bottom portion of the outer case, wherein the bottom cover includes:
in a state of being fixed to the outer case, accommodate a bottom surface of the outer case and the image display device to isolate the bottom surface of the outer case and the image display device from an external space of the outer housing; and
fins on an outer surface thereof;
a control circuit configured to control the image display device; and
a main substrate equipped with the control circuit, wherein
the outer case includes, on a surface facing the bottom cover, a substrate holding surface for holding the main substrate, and
a heat conductive portion having a thermal conductivity higher than that of air is between the control circuit on the main substrate held by the substrate holding surface and the bottom cover.