| 摘要 |
The optical module has a semiconductor light emitting device, a lens, a holder for the device and the lens, and a receptacle core onto which a ferule of a counter optical plug is to be fitted. When the optical plug is connected, the semiconductor light emitting device is optically coupled with an optical fiber in the ferule by the lens. A step portion which forms a circular opening with setting the optical axis as the center axis and which eliminates coupling undesired light is disposed at a position which is on an emission side of the lens with respect to a contacting position of the-holder and the lens. Preferably, the optical module satisfies the following expressions:0.9< phi /(NAxL1)<1.3 and L2<L1/2where phi is a diameter of the circular opening, NA is a numerical aperture of the optical fiber, L1 is a distance between an opening end on the side of the lens and the optical fiber, and L2 is a distance between an end of the lens and the opening end on the side of the lens.
|
