Optical transmission and receiving module and optical communication system using the same
AssigneeHitachi, Ltd.
InventorsKunikazu Ohnishi, Masayuki Inoue, Yoshio Suzuki, Yukio Fukui
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AssigneeHitachi, Ltd.
InventorsKunikazu Ohnishi, Masayuki Inoue, Yoshio Suzuki, Yukio Fukui
Estimating the term…
A bidirectional optical transmission and receiving module of a simplified structure and an optical communication system using the same. The optical transmission and receiving module includes a light emitting device and a light receiving device disposed with in a same package having an opening covered with a cover glass sheet, and a holographic diffraction grating provided on a top or lower surface of the glass sheet. In transmitting operation, a light beam emitted from the light emitting device passes through the diffraction grating to be concentrated onto an end face of an optical fiber by a lens. In receiving operation, a received light beam emanated from the end face of the optical fiber reaches the diffraction grating via the lens to be thereby diffracted. A plus-sign primary diffracted light beam resulting from the diffraction is concentrated onto a light detecting surface of the light receiving device. Signal as transmitted through the optical fiber in the form of signal light can thus be received.
An optical transmission and receiving module, comprising:
An optical communication system including an optical transmission and receiving module which comprises a light emitting device, a photodetector, an optical element for introducing a light beam emitted from said light emitting device to a predetermined optical transmission path, a housing for accommodating at least said light emitting device and said photodetector, a window formed in said housing and provided with a transparent member for passing light therethrough in opposite directions, and a diffraction grating having grooves of rectilinear or curvilinear traces and provided on an upper surface or a lower surface of said transparent member, said light emitting device and said photodetector being provided on the same side with respect to said transparent member.
Dependencies are inferred from the claim text.