Soyo STH-DCAM ユーザーズマニュアル

STH-DCAM U

SER

’

S 

M

ANUAL

 

 

 

 

 

 

 

 

 

 

 

 

 

2001 V

IDERE 

D

ESIGN

 

Range resolution is the minimum distance the stereo system can distinguish.  
Since stereo is a triangulation operation, the range resolution gets worse 
with increasing distance from the stereo head.  The relationship is: 

∆

=

∆

2

, 

where b is the baseline between the imagers, f is the focal length of the lens, 
and 

∆

is the smallest disparity the stereo system can detect.  For the STH-

DCAM, b is 90 mm, and 

∆

is 0.35 um (pixel size of 5.6 um, divided by 

the interpolation factor of 16).   

 

Figure 4-1 plots this relationship for several focal lengths.  At any distance, 
the range resolution is inversely proportional to the focal length. 

 

 

The field of view is completely determined by the focal length, given a 
fixed imager.  The formulas for the FOV in horizontal and vertical 
directions are: 

)

/

792

.

1

arctan(

2

=

 

)

/

344

.

1

arctan(

2

=

 

where f is in millimeters.  For example, a 4.0 mm lens yields a horizontal 
FOV of 48 degrees.  The following table shows the FOV for some standard 
focal lengths. 

 

 

2.1 mm 

81 deg 

65 deg 

4.0   

 

48

37

8.0   

 

25

19

8