Patent ID: 7579698

Claim:
A semiconductor photodetector including a semiconductor light receiving element having a light receiving surface and having spectral sensitivity in wavelengths from at least a visible light region to infrared region in wavelength ranges approximately between 400 nm to 1100 nm, and an optical transmitting resin for sealing at least the light receiving surface of the semiconductor light receiving element, said optical transmitting resin having a transmissivity to light in the visible light region greater than 20% over at least a portion of the wavelength range between 400 nm and 700 nm and blocking light in the infrared region such that the transmissivity of the resin is less than 10% over at least most of the wavelength range of 700 nm to 1100 nm: wherein said optical transmitting resin is boride of one or more elements selected from La, Pr, Nd, Ce, Y, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo or W and is formed by dispersing micro particles whose particle diameter is not more than approximately 100 nm in a transparent resin.