Ophir Optronics Ltd QSR ユーザーズマニュアル

To configure an average reading for a photodiode head, refer to Averaging the 
Measurements in Chapter 4 – Measuring with the Thermopile Head. 

StarLab can be optimized to achieve the most accurate and efficient results. This 
section describes the optimization settings available for the photodiode head: 
applying an offset, zeroing the instrument, and setting line frequency. 

Ophir’s unique dual-detector heads detect and subtract 98% of background light. 
The residual background signal can be removed using the Offset feature. The 
Offset feature subtracts background light from the signal.  

For example, the display reads 0.1 µW when the laser is blocked, and 20.5 µW 
when laser power is applied. In this case, the true power is 20.5 - 0.1 = 20.4 µW. 
To subtract the background, apply an offset while the laser is blocked. The 
display will now read zero, and the 0.1 µW background will be subtracted from 
all subsequent readings. The laser power reading will be 20.4 µW.  

1.  Click 

 in the Graph Configuration Area. The Offset button 

toggles to Offset On when the Offset is activated. 

The Offset value is displayed under the main measurement reading in the 
Numeric Display Area. 

1.  Click 

 in the Graph Configuration Area. The Offset value is 

cancelled.  

disconnect the head while the head is in power measurement mode. If 
the instrument still shows a similar reading even when the head is not 
connected, zero the instrument. For information on zeroing the 
instrument, refer to Zeroing the Instrument in Chapter 4 – Measuring 
with the Thermopile Head.