A question for the shooters here about laser sights.

[etpm]

I have a laser pointer sight, the type that clamps to the barrel and projects a laser beam to the target. I was cleaning the front window and noticed that the window was glued in at an angle. About 15 degrees. I looked carefully and the window is not glued in at that angle mistakenly, the sight is machined that way. That much of an angle is surely not a mistake, is not shoddy manufacturing. The instructions that came with the sight made no mention of this window being at an angle. But it is a cheap sight that I bought just for fun, unlike the Holosun on my pistol, so I'm not surprised that the instructions didn't mention the angled window. Does anybody here know the reason for the angle?
Eric

 

[CalG]

Each window surface will have some reflection due to the refractive index difference between glass (1.52) and air (1) (Fresnel said so, trust him!)

If the window were perpendicular with the LASER beam, you very well would see multiple "spots" on your target as the window glass reflections walked across the window surfaces (BOTH SIDES!)

Go ahead, shine your LASER on a typical home window and try to keep track of all the "spots".

The window angle makes sure these superfluous dots are well away from the target!

 

[etpm]

Each window surface will have some reflection due to the refractive index difference between glass (1.52) and air (1) (Fresnel said so, trust him!)

If the window were perpendicular with the LASER beam, you very well would see multiple "spots" on your target as the window glass reflections walked across the window surfaces (BOTH SIDES!)

Go ahead, shine your LASER on a typical home window and try to keep track of all the "spots".

The window angle makes sure these superfluous dots are well away from the target!

Thank you. After my post an your's I looked online and apparently this angle is called the "BREWSTER'S" angle.
Thanks Again,
Eric

 

[CalG]

Well, Brewster's angle is applicable to achieve a single plane of polarization.
Frustrated Total Internal Reflection goes hand in hand

The Brewster's angle for GLASS to AIR is around 56 degrees.

Not likely applied to your LASER Sight/

 

[etpm]

Well, Brewster's angle is applicable to achieve a single plane of polarization.
Frustrated Total Internal Reflection goes hand in hand

The Brewster's angle for GLASS to AIR is around 56 degrees.

Not likely applied to your LASER Sight/

Yeah, 56 degrees is way more angle than my laser sight has, so I guess it's not at the Brewster's angle.
Eric