US 6,556,601 B2 · Method for compensating for output of semiconductor luminous device and apparatus therefor

Abstract

A variation in optical output of a semiconductor luminous device outputting an optical signal to an optical fiber which is caused due to a variation in ambient temperature and an end of a life thereof capable of being compensated for without measuring the optical output. An output variation quantity H0(Ta) of the semiconductor luminous device due to the ambient temperature Ta is operated in a step S2. In a step S4, an output reduction quantity ST of the semiconductor luminous device obtaining by accumulating an output reduction ST thereof per unit time due to a deterioration of the device is provided. In a step S5, it is judged that a life of the device reaches an end when the output reduction ST exceeds a reference value ST0. When the former fails to exceed the latter, a variation quantity IH(Ta) of a drive current command value due to the ambient temperature Ta and a current reduction quantity IST(ST, dST) determined due to a deterioration of the device are operated in a step S6. A drive current Id for driving the semiconductor luminous device is determined on the basis of a sum Is of the current command value Ic, the current variation quantity and the current reduction quantity. An output of the device is compensated for by repeating steps S1 to S9.

Claims10

Dependent claims

A method for compensating for an output of a semiconductor luminous device for outputting an optical signal to an optical fiber wherein an output variation quantity of the semiconductor luminous device due to a variation in ambient temperature is provided, to thereby adjust a drive current of the semiconductor luminous device, comprising the steps of:

obtaining an output reduction by computation of the semiconductor luminous device per unit time owing to a deterioration of the semiconductor luminous device depending on a current fed to the semiconductor luminous device and the ambient temperature,
obtaining an output reduction quantity of the semiconductor luminous device based on a life of the semiconductor luminous device using a cumulative value of the output reduction;
and
adjusting the drive current on the basis of the output variation quantity and the output reduction quantity.

1 more element

An output compensation apparatus for a semiconductor luminous device for outputting an optical signal to an optical fiber, comprising:

a semiconductor drive circuit for feeding said semiconductor luminous device with a drive current on the basis of a current command value;
a temperature sensor for detecting an ambient temperature of said semiconductor luminous device;
a temperature compensation means for providing an output variation quantity of said semiconductor luminous device depending on a variation in said ambient temperature using an output of said temperature sensor;
an addition point for adding a compensation quantity based on said output variation quantity to said current command value to provide an added value and feedback it to said semiconductor drive circuit;
a life-based reduction operation means for obtaining an output reduction by computation of said semiconductor luminous device per unit time owing to a deterioration of said semiconductor luminous device depending on a current fed to said semiconductor luminous device and said ambient temperature to provide an output reduction quantity of said semiconductor luminous device based on a life thereof using a cumulative value of said output reduction;
and
an addition means for adding said output variation quantity and output reduction quantity to each other to provide said compensation quantity.

4 more elements

Dependencies are inferred from the claim text.

Method for compensating for output of semiconductor luminous device and apparatus therefor

Life of this patent

Method for compensating for output of semiconductor luminous device and apparatus therefor

Life of this patent

Abstract

Claims10