Vzense DS77 Lite, Руководство пользователя

Страница: 14 / 37

14
3.7
Optical Specifications
3.7.1
Field of View
The field of view refers to the view angle of the ToF products. The TOF sensor’s aspect ratio
is 4:3, typically the horizontal field of view is larger than the vertical field of view. The DFOV
(see figure below) is the angle subtended by the diagonal of the camera sensor onto the center
of the lens.
The definition of HFOV and VFOV can be exchanged, i. e. we can rotate the camera sensor
to have larger FOV at vertical direction.
Typical FOV of DS77 Series is 70°*55°, we can do FOV customization if the customer requires,
and reasonable NRE fee shall be charged.
3.7.2
Wavelength of the VCSEL
All our product are based on VCSEL laser. We have variety choices according to the lens FOV
and wavelength. The laser FOV must match to the lens FOV, and the wider FOV products
need stronger power, therefore higher power consumption. Even with higher power supplied,
the laser power per angle of the wider FOV product may be reduced, so normally the maximum
distance of wider FOV products is shorter than narrower FOV products.
As for the wavelength, we have 850nm and 940nm laser selection. Because of the silicon
process based ToF sensor, the ToF sensor’s QE of 850nm is much better than it of 940nm.
That means normally 850nm product can reach longer distance or the same distance with
lower power consumption;
But the 940nm wavelength has better performance under strong sunlight, especially when the
ambient light is stronger than 20K LUX.
Below are the laser choices we can provide, if you have other needs, please let us know.
H70°, V55°--- 2W, 940nm
H110°, V85°--- 2W, 850nm