ADNS-3050 Avago Technologies US Inc., ADNS-3050 Datasheet - Page 18

• Manufacturer Part Number: ADNS-3050
• Description: Optical Sensors - Board Mount Optical Nav Sensor
• Manufacturer: Avago Technologies US Inc.

Specifications of ADNS-3050

• Lead Free Status / Rohs Status: Details

SQUAL
Access: Read
Data Type: Upper 8 bits of a 9-bit unsigned integer.
USAGE:
18
Figure 20. Squal values (white paper)
Figure 21. Mean squal vs. Z (White Paper)
Field SQ7
-10
SQUAL (Surface Quality) is a measure of the number of valid features visible by the sensor in the current
frame. The maximum SQUAL register value is 128. Since small changes in the current frame can result in
changes in SQUAL, variations in SQUAL when looking at a surface are expected. The graph below shows 800
sequentially acquired SQUAL values, while a sensor was moved slowly over white paper. SQUAL is nearly
equal to zero, if there is no surface below the sensor. SQUAL is typically maximized when the navigation
surface is at the optimum distance from the imaging lens (the nominal Z-height).
60
50
40
30
20
10
60
50
40
30
20
10
0
0
Bit 7
1.6
Address: 0x05
Reset Value: 0x00
1.8
6
SQ6
2
Distance from Lens Reference Plane to Tracking Surface - Z (mm)
5
SQ5
2.2
Mean SQUAL vs Z (White Paper)
Squal (White Paper)
2.4
4
SQ4
Count
2.6
3
SQ3
2.8
3
2
SQ2
3.2
Avg-3sigma
Avg
Avg+3sigma
1
SQ1
0
SQ0