THORLABS Redstone OSA305 - Page 12

Redstone™ Optical Spectrum Analyzer Chapter 4: Description
Rev C, January 21, 2022 Page 8
Figure 2. Resolution as a Function of Wavelength
The sensitivity of the instrument depends on the electronic gain used in the sensor electronics. Since an
increased gain setting reduces the bandwidth of the detectors, the instrument will run slower when higher gain
settings are used. Figure 3 and Figure 4 show the dependence of the noise floor on the wavelength and OSA
model.
Figure 3. Noise Floor in Absolute Power Mode
0 2 4 6 8 10 12
10
0
10
1
10
2
10
3
10
4
10
5
OSA20xC, High
OSA20xC, Low
OSA305, Low
OSA305, Medium Low
OSA305, Medium High
OSA305, High
Resolution in Spectrometer Mode
Resolution (pm)
Wavelength (µm)
1 10
-105
-95
-85
-75
-65
-55
-45
OSA305
OSA201C
OSA205C
OSA203C
OSA207C
OSA202C
OSA Noise Floor in Absolute Power Mode
Noise Floor (dBm)
Wavelength (µm)
0.3 20