Basic Characteristics and Processes

Photoconductivity i.e. the change of the conductivity under the action of light Act can be described by the expression 

It can be clearly seen that the photocurrent has to be linear function of the voltage, if p and x do not depend on the voltage. Really there are some mechanisms when this linearity does not hold. For example, if the voltage reaches the value, obeyed by the condition 

If V Fxe/C the transition times become equal to the time of the dielectric 

The width of the photoconductor band transmission (AB), corresponding to the time constant of the photoconductor response, can be written AB = 1 /27ix 

In highly resistive photoconductors l/2nxr, at low light intensity, may be less than unity. This means that photoconductors with a high gain coefficient will have a very slow response time. 

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