Datasheet

Chapter 3

Starter Kit (pulser, temperature

controller, etc...)

This chapter discusses properties of the Starter Kit, used for pulsed mode lasers.

3.1 Operation of TE cooler

3.1.1 What is the dissipated heat of a pulsed QC laser?

Pulsed QC lasers in general work at threshold voltages of 9V...12V and threshold cur-

rents of 1A...3A, with maximum values of up to 25V and 10A. The peak power during

operation therefore can vary in the range of about 10W...1000W. Depending on duty

cycle, the mean dissipated power normally is in the range of some Watts.

3.1.2 What temperatures can be reached with the TCU-151?

Normally, the TCU-151 is shipped with current limitation of 5A and alarm value of

65C. Depending on the heat sink used, temperatures between -35 and +60C may be

reached. Very high and low temperatures induce more stress on the Peltier elements

and therefore accelerate ageing.

3.2 Important points concerning LDD pulsers

3.2.1 What are the possible pulse lengths and duty cycles?

The pulse driver LDD100 can amplify pulses with lengths of 5ns...300ns and minimal

period of 100ns. Maximal duty cycle is 50% (with reduced stability and not continu-

ously to prevent overheating, up to 90%). The pulse generator TPG128 is capable of

generating pulses with lengths of 20ns...200ns (with reduced stability down to 10ns)

and period of 0.2µs...10.5µs. Duty cycle can vary in the range of 0.1%...80% (with

reduced stability up to 95%).

In combination with LDD100, only 50% duty cycle can be reached, since the power

supply in TPG128 which is feeding LDD100 is not speciﬁed for higher values. Provide

external power source for LDD100 if more than 50% is needed. In any case, contact

Alpes Lasers SA ﬁrst, if duty cycles of more than 2% are needed.