BI-DIRECTIONAL LINK SUBMODULE WITH HOLOGRAPHIC BEAMSPLITTER

摘要

The link has passively aligned bidirectional optics and devices mounted on a silicon substrate (300) having selectively etched grooves to effect the alignment of an optical fiber (409) to the optical elements of the link, as well as to effect mounting of the optoelectronic devices (laser, detector) in proper optical alignment. The bidirectional link of a first embodiment uses a first wavelength for the transmission mode and a second wavelength for the reception mode to minimize optical crosstalk between the reception and transmission signals which would result in signal distortion. Accordingly, the use of wavelength dependent elements such as holograms (406, 407, 408) and dichroic materials is required. To achieve this result in a relatively small volume of space, a holographic plate (303) is disposed above the silicon waferboard having holograms and a dichroic element fabricated thereon. The holograms effect the wavelength selective directing of the transmit and receive modes to and from the respective elements as well as the necessary focusing. The dichroic element provides wavelength dependent filtering for the detector.