Abstract: A structure in which first to third diodes cause signal beams which are produced by modulating image signals to be incident upon corresponding first to third light deflection scanning sections. The first to third light deflection scanning sections perform line scanning operations using the incident light signal beams. First to third light amplifiers amplify the light signal beams used for the line scanning to necessary brightnesses. A light-wave synthesizer synthesizes the amplified light signal beams into one light beam. A light post scanning section performs frame scanning using the synthesized light beam in order to project it onto a screen. Accordingly, it is possible to display a highly bright image at a low cost on a large screen that realizes high definition and color reproducibility.

Abstract: A structure in which first to third diodes cause signal beams which are produced by modulating image signals to be incident upon corresponding first to third light deflection scanning sections. The first to third light deflection scanning sections perform line scanning operations using the incident light signal beams. First to third light amplifiers amplify the light signal beams used for the line scanning to necessary brightnesses. A light-wave synthesizer synthesizes the amplified light signal beams into one light beam. A light post scanning section performs frame scanning using the synthesized light beam in order to project it onto a screen. Accordingly, it is possible to display a highly bright image at a low cost on a large screen that realizes high definition and color reproducibility.

Abstract: To be able to receive a laser beam having a predetermined intensity even if lengths of optical fibers differ, a laser beam transmitted from a counterpart of communication is received by a photodiode, an electric signal produced thereby is amplified by an amplifying unit and thereafter, a peak value of the signal is detected by a peak hold unit, a differential amplifying unit calculates a difference between an output signal from the peak hold unit and a reference level (Rx. Ref), forms a control signal based on the difference and outputs it to APC via a selector, APC controls an LD drive unit in accordance with an output from a photodiode where a portion of a laser beam emitted from LD is incident and the signal outputted from the differential amplifying unit, and the LD drive unit amplifies transmitted data (Tx. Data) in accordance with a signal outputted from APC thereby driving LD.

Abstract: A wave combining apparatus for semiconductor lasers includes first and second dichroic mirrors for combining laser beams having the same direction of oscillation by waveform division, respectively, and a polarizing beam splitter prism for combining the first and second resultant beams into a single, combined waveform.