- #1
rich333
- 7
- 0
I am experimenting with a CIS from a document scanner (basically a row of photo sensors).
I want to detect the position of an object as it passes the scanner bar. Initially in one dimension - x along the CIS.
If the object is always a set distance from the light bar, I can provide illumination with a line laser or row of leds and the object will cast a shadow as it passes through the light. The position of the object along the light bar can be detected.
However if the object can be close to the light source or close to the CIS, it's shadow will be cast in different places.
In effect I need a row of light beams such that the object shadow is cast in the correct x direction, regardless of it's y position. Is that even possible?
If I add a second CIS and then find the objects Y position, I guess I can calculate it's X and Y position, even with light sources that are effectively single point?
The ultimate goal is to find the X,Y position of the object as it passes the two CIS scanner bars.
Any ideas most welcome!
(Simple sketch attached)
I want to detect the position of an object as it passes the scanner bar. Initially in one dimension - x along the CIS.
If the object is always a set distance from the light bar, I can provide illumination with a line laser or row of leds and the object will cast a shadow as it passes through the light. The position of the object along the light bar can be detected.
However if the object can be close to the light source or close to the CIS, it's shadow will be cast in different places.
In effect I need a row of light beams such that the object shadow is cast in the correct x direction, regardless of it's y position. Is that even possible?
If I add a second CIS and then find the objects Y position, I guess I can calculate it's X and Y position, even with light sources that are effectively single point?
The ultimate goal is to find the X,Y position of the object as it passes the two CIS scanner bars.
Any ideas most welcome!
(Simple sketch attached)