초록 ▼

An optical transmission apparatus is provided which has an LD of single longitudinal mode. A bias current of the LD is set at its threshold current. A current obtained by amplitude modulation of a signal to be transmitted is superposed on the bias current. The LD is then set in the multimode, so tha

An optical transmission apparatus is provided which has an LD of single longitudinal mode. A bias current of the LD is set at its threshold current. A current obtained by amplitude modulation of a signal to be transmitted is superposed on the bias current. The LD is then set in the multimode, so that the apparatus can transmit a high-quality signal with reduced modal noise and distortion during multimode fiber transmission.

대표청구항 ▼

An optical transmission apparatus comprising: clamp means for clamping an input video signal; high-frequency oscillator means for producing a high-frequency oscillation signal; amplitude modulator means for modulating the high-frequency oscillation signal with the clamped video signal to produce a m

An optical transmission apparatus comprising: clamp means for clamping an input video signal; high-frequency oscillator means for producing a high-frequency oscillation signal; amplitude modulator means for modulating the high-frequency oscillation signal with the clamped video signal to produce a modulated video signal; light emitting means for producing an output light signal in response to said modulated video signal from said amplitude modulator means; variable current source means for adding a current to said modulated video signal; said variable current source means providing a bias current to said light emitting means for substantially linear operation of said light emitting means, said bias current being substantially equal to a threshold current to adjust the current of said modulated video signal in response to said output light signal; multimode optical fiber means for transmitting said output light signal from said light emitting means.