M8Measure.spt

Graphs | Data | Data Interpretation

This script measures the M8 power sensor readings as the laser current is increased up to the nominal laser current setting.

M8Measure Graphs

M8Measure.ps: This graph shows the M8 readings versus laser current.

M8Measure Data

There is one output file, M8Measure_data.txt. This file contains five data columns:

1. Laser current in Amps
2. Number of samples taken at this laser current, typically 128
3. The average M8 sensor reading, in raw ADC units
4. The maximum M8 sensor reading, in raw ADC units
5. The minimum M8 sensor reading, in raw ADC units

Interpretation of the Data

Check the graph for two things: the sensor output should be reasonably linear, and the sensor should not saturate. As the write laser does not start lasing right away (it tends to start around 10A) the graph will not run through the origin. If the reading at nominal laser current is less than 2000, then there could be problems with the sensor signal being too low. Also, if the maximum reading is above 3500, then there could be problems with the sensor signal being too high. Ensure that the sensor isn't saturating. See <%= htmlCedirLinkAlternateTitle(20695, "Note 6") %> .