3 The application of optoelectronic components in the IRMSS
The application of optoelectronic components is involved in many places with different model type and working states in the IRMSS of CBERS.

K2

V2mas - V1max ---------------- V1max

x 100 %

or

K3

V2mas - V1max ---------------- V1max

x 100 %

V_1max - the initial maximum of signal output (V),

V_2max- the maximum of signal output after radiation (V),

V₀ - the value of the linear dynamic range of signal output (V).

Note : The value of the linear dynamic range of signal output is related to the component itself and the test circuit.

The relations between the variety of signal output following radiative dose of emitters and phototransistor during radiation are given below, see figure 4 and figure 5.


Figure 4: The Curve for Emitters

Figure 5: The Curve for Phototransistors
In the SMA (Scan-mirror Assembly), the coupling pairs formed by optoelectronic components and logical circuit supply the IRMSS with forward, backward and forward-to-backward scanning position signals. The switching characteristic of the components is used here. Whether liner or saturate sector the phototransistor works in, the design requirements can be met if the coupling pairs meet the needs of logical circuit after radiation.

The optoelectronic components in the SLC (Scan-line Corector) and the RLD (Revolving Light Diaphragm) are used the same way as the SMA. The SLC and shutter position signals which are synchronous with scanning signals which are synchronous with scanning signals will be available after frequency-lock and phase-lock circuits in this application.

Emitters are first used to be light source of the optical system in the SAM (Scan-angle Monitor) which can supply the IRMSS with standard dynamic scan-angle position signals. The variety of signal output must be measured definitely after radiation in this application.

The anti-radiation performance of the optoelectronic components can be measured with their applied circuit by developing the study of measuring method, and the results of measurement are feedback to the design itself, then the working margin and reliability of the system may be improved with components choosing, anti-radiation protection and signal compensating measures.

4 Conclusion
The anti-radiation capabilities of optoelectronic components are different because of their different materials and manufacture techniques.

The measuring method mentioned above is in common use and can be widely applied to luminescent units, photosensitive units or their combination.

In the IRMSS, all subsystems in which optoelectronic components are used have met the operating demands.