Moving a laser closer to a glass window to reduce reflection?

Is it true that the closer the laser beam is to the glass window the better the measurement I will get (since there is less reflection?)?

The laser has the following specifications:
Light source: Laser red, class 1 (EN 60 825-1-2007)
Light spot diameter: typ. Ø 15 mm at 10 m distance

The rest of the specifications can be found in the following data sheet:
http://www.sensorsincorporated.com/uploaded/Doc/DT50 Data Sheet.pdf

a window will reflect the same amount, regardless of distance between source and window.

In other words, a window will reflect a certain % of power.
1W laser 5mm away from window will lose the same % of power as if it were 10m away.

BShanahan is correct. However, do note that the ANGLE at which the light strikes the glass DOES affect the amount of reflected light. In particular, if the laser (collimated) is shined at glass at a large angle from the perpendicular, then substantially more will be reflected than if it were perpendicular to the glass. (Note that this is only true for randomly polarized lasers. If lasers are p-polarized, up until the Brewster angle, p-polarized lasers decrease their reflectivity, and then afterwards sharply increase.

In this way, you will get slightly more reflection when the laser is not focused at infinity.

tried to rep, gotta spread some love first. ^good info! :wave: