Abstract:
The spectral linewidth enhancement factor and frequency responses of electro-absorption-type optical-intensity modulators, especially InGaAs/InAlAs MQW modulators, are de...Show MoreMetadata
Abstract:
The spectral linewidth enhancement factor and frequency responses of electro-absorption-type optical-intensity modulators, especially InGaAs/InAlAs MQW modulators, are described. A method of exactly estimating the value of the alpha factor is presented under the nonlinearity of extinction-ratio characteristics. For measuring the frequency response of modulators, the sideband strength of the modulated output light with an optical spectrum analyzer, is analytically compared with the microwave power of photodiode direct detection with an electrical spectrum analyzer.<>
Published in: Journal of Lightwave Technology ( Volume: 10, Issue: 1, January 1992)
DOI: 10.1109/50.108739
Citations are not available for this document.
Cites in Patents (4)Patent Links Provided by 1790 Analytics
1.
Mayer, Hans-Peter; Baums, Dieter, "OPTICAL MODULATOR CIRCUIT"
Inventors:
Mayer, Hans-Peter; Baums, Dieter
Abstract:
A circuit arrangement is presented for an optical modulator with an optical modulator diode (MD) driven in the blocking direction which, in addition to a shunt resistor (RN) wired in parallel with the modulator diode, contains a damping resistor (RD) wired ahead of the modulator diode, for attenuating unwanted reflections. The damping resistor is preferably wired ahead of the parallel circuit of modulator diode and shunt resistor, and forms part of the terminal resistance of the connecting line carrying the modulation signal (U.sub.m).
Assignee:
ALCATEL N V
Filing Date:
07 December 1995
Grant Date:
11 August 1998
Patent Classes:
Current U.S. Class:
359245000, 330055000, 385002000
Current International Class:
G02F0010300000, H03F0032600000
2.
Mayer, Hans-Peter, Dr.; Baums, Dieter, Dr., "Optical modulator circuit"
Inventors:
Mayer, Hans-Peter, Dr.; Baums, Dieter, Dr.
Abstract:
Optical modulator circuit, e.g. for use as optical switch The circuit contains an optical modulator diode (MD) driven in the blocking direction. Light to be modulated is passed via the optical modulator diode, which is connected in parallel with a shunt resistance (RN) for impedance matching to a circuit providing the modulation signal (Um). A damping resistance (RD) is connected in series with the optical modulation diode and/or with the parallel circuit of optical modulator diode and shunt resistance. The values of the damping and shunt resistances are selected so that their sum forms an optimal value of terminating resistance for the circuit providing the modulation signal.
Assignee:
ALCATEL SEL AKTIENGESELLSCHAFT,
ALCATEL N V,
Filing Date:
30 November 1995
Grant Date:
12 June 1996
Patent Classes:
Current International Class:
G02F0010100000
3.
Onishi, Masaru; Suzuki, Kazuhiro, "ELECTRIC FIELD ABSORPTION LIGHT MODULATION DRIVING APPARATUS AND METHOD HAVING IMPROVED FEATURE TO ELIMINATE NOISE FROM OPTICAL OUTPUT"
Inventors:
Onishi, Masaru; Suzuki, Kazuhiro
Abstract:
An electric field absorption light modulation unit includes a light emission device for emitting light and a modulation device for varying a light transmittance thereof of light applied by the light emission device so as to provide the light as a result of modifying thereof. A driving signal generating unit coupled with the electric field absorption light modulation unit generates a driving signal to be applied to the modulation device from an input information signal by making the modulation device vary the light transmittance thereof, and the driving signal generating unit provides the driving signal so that the driving signal in a fluctuation range in which an undesirable level fluctuation may be present, corresponds to a constant working range of the modulation device, the light transmittance thereof staying at a constant value in the constant working range.
Assignee:
FUJITSU LTD
Filing Date:
30 November 1991
Grant Date:
31 May 1994
Patent Classes:
Current U.S. Class:
372038020, 359276000, 359320000, 372033000, 455106000
Current International Class:
H01S0031000000, H04B0100400000, G02F0010100000, G02F0012900000, G02F0012900000
4.
Onishi, Masaru, c/o FUJITSU LIMITED; Suzuki, Kazuhiro, c/o FUJITSU LIMITED, "Electric field absorption light modulation driving apparatus and method"
Inventors:
Onishi, Masaru, c/o FUJITSU LIMITED; Suzuki, Kazuhiro, c/o FUJITSU LIMITED
Abstract:
An electric field absorption light modulation unit (3) includes a light emission device (1) for emitting light and a modulation device (2) for varying a light transmittance thereof of light applied by the light emission device (1) so as to provide the light as a result of modifying thereof. A driving signal generating unit (10 and 11) coupled with the electric field absorption light modulation unit (1) generates a driving signal to be applied to the modulation device (2) from an input information signal by making the modulation device (2) vary the light transmittance thereof, and the driving signal generating unit (10 and 11) provides the driving signal so that the driving signal in a fluctuation range in which an undesirable level fluctuation may be present, corresponds to a constant working range of the modulation device (2), the light transmittance thereof staying at a constant value in the constant working range.
Assignee:
FUJITSU LTD
Filing Date:
29 October 1992
Grant Date:
05 May 1993
Patent Classes:
Current International Class:
H04B0100400000, G02F0010100000, G02F0010150000, H01S0050600000, H04B0100600000, H04B0101420000, H04B0101520000
