very high collimated lens.

[hiren.dave@bhuved.com]

Hi,

I want to design a project named "high range laser distance finder". Here, my laser is not collimated and its spread. So i want highly collimated lens that can maintain laser beam to infinite range.

is it possible? or it must maintain laser beam up to 1 km.

 

[Sceadwian]

You can't collimate a diverging beam to infinite range perfectly, you can focus it but you have to have a defined end point and allowed beam width (to avoid confusion with barriers)

The simplest way to collimate a diverging source is with a tube made out of a material which will absorb the frequency that the source produces. You lose a lot of amplitude this way though; you could diverge it further with one lens, refocus it down to a smaller point with a second lens, and use a third lens to refocus it from the smaller point outwards to the target distance, but this is optically complex.

A LOT more details on your part would be required to recommend anything specific. Specifically you'd need to know the exact divergence of the beam you have and it's width, and define desired target distance.


Keep in mind, a laser range finger over 1km is going to be virtually useless if you don't have some really high powered optics to aim it, and the optics and the laser source need to be calibrated for accuracy. It's also going to need a pencil thin beam that is highly collimate, and this is not easy.

 

[ericgibbs]

Hi,

I want to design a project named "high range laser distance finder". Here, my laser is not collimated and its spread. So i want highly collimated lens that can maintain laser beam to infinite range.

is it possible? or it must maintain laser beam up to 1 km.

hi hiren,
Whats the part number or datasheet for your laser.??

Depending upon your laser type, it is possible to refocus a diverging beam by using a lens, not a collimator tube.

Please post more details of the project, for example:
you say range finder, this means a receiver will be required at the transmitting end.

The receiver would also require a lens in order to optimise the echo signal/range,

Will it be a pulsed laser or continuous, IR or visible light.??

E.

 

[jpanhalt]

Since this is a project, it is important to distinguish between the questions of obtaining theoretically perfect collimation and what might work. As Eric points out, to answer the latter, more information is needed.

Here is a nice discussion of theoretical limitations and practical solutions with worked out examples: https://www.newport.com/Focusing-and-Collimating/141191/1033/content.aspx

This relevant patent also popped up:
**broken link removed**
John