# how to scan a diode laser wavelength in certain range?

Is it possible to scan a sacher diode laser in certain wavelength range?

For example, when piezo offset is 0 volt, the wavelength of laser (read from a wave-meter) is x. When I set the piezo offset to -6 volt, I see laser wavelength shifting to x-x'. I would assume, when I change piezo offset from 0 to -10v, wavelength of diode laser is changing continuously. But I only see wavelength change starting at -6 volt.

So my question is, how to scan a diode laser wavelength in certain range?

• If you're asking how to use a tunable laser that you bought, that's more of an engineering problem than physics. And also you need to tell us exactly what product you are using if you want us to have any hope of helping you. – The Photon Oct 7 '15 at 2:01
• AFAICT, Sacher has at least 7 different tunable laser models available. – The Photon Oct 7 '15 at 2:03
• It is "Manual Tunable Littman/Metcalf Diode Laser System - Lion". I would assume the ones using piezo to change wavelength is quite general in their products, or even other brands. Someone please help. Thanks! – Sean Oct 7 '15 at 2:20
• The tunable laser in my lab has a 0 to 100 V tuning range. If voltages below 6 V didn't change the wavelength, the solution would just be to use the range from 6 to 100 V. – The Photon Oct 7 '15 at 2:23
• The one I'm using has piezo offset from -13 to 13 V. However, from -7 to 0 V, the wavelength is just the same. From 0 to 13 V, the laser power is too low for me to do anything useful. And in the -13 to -7 V range, the wavelength only changes 3-4 times. Considering that I set the piezo step low as 0.01 V, I would assume the wavelength should change quite continuously. Do all these sound normal to you? What would be wrong? Thanks! – Sean Oct 7 '15 at 2:30