OPTICAL SENSING DEVICE OF CONTROLLING INCIDENT ANGLE BY USING ANGLE OF HOUSING COVER

The present invention relates to an optical sensing device capable of controlling incident angle by using gradient of a housing cover. The optical sensing device recognizes finger gesture of a user by being installed in a portable device. The optical sensing device includes: a light source for emitting a light; a prism for reflecting the light emitted from the light source in a constant angle and then emitting the reflected light to the outside; a sensing part for irradiating the light incident by being reflected from the prism; and a housing cover having a light transmission part transmitting the light as an upper cover of the optical sensing device. The light transmission part of the housing cover has a slope which is sloped in a constant angle and has different thickness for one side and the other side, and the propagation path of the light is adjusted by refraction due to the slope of the light transmission part. According to the present invention, the optical sensing device has high operation reliability as being realized in thin thickness, and can contribute to slimness of a portable device like a mobile phone and a note book.