Sony Corporation

Koji Aoyagi

Kuniharu Onozuka

Toshio Kimura

A power circuit is provided so that a charge can be normally driven even during replacement of a first battery. This power circuit comprises: first and second batteries for driving a charge; a first battery voltage detection means; a first switch for controlling a second battery power supply path based on an output of the voltage detection means; an overcharge prevention means for preventing an overcharge for the secondary battery caused by the first battery; and a switch controlled by an output of the overcharge prevention means.

Power circuit, power supply method, and electronic device

Disclosed is a head-mount type display apparatus having an optical system which is of the back-irradiation type by which the user can see an extremely high-quality video image and by which the user makes only in-focus adjustment thereby improving operation convenience. The head-mount type display apparatus includes at least two optical systems each including a light source, a LCD through which the light from the light source is passed, a reflecting plate which reflects the light passing through the LCD, a screen on the back side of which the reflected light from the reflecting plate is focused to form an image and a lens by which the light from the screen is focused to form an image at a viewing point, and a head-mount type member for supporting the two optical systems which are opposed to left and right eyes. According to the preferred embodiment, interference and distortion in the projected images arising from the image of the edges of the LCDs is substantially reduced.

Growing community of inventors

Kanagawa, Japan

Koji Aoyagi