This is a repost from a separate thread.
I should have posted it here in the first place.
This clearly illustrates the failings of the LaserVue.
EJKrew got it mostly right. The parabolic mirror however is not responsible for the glowlight hot spot. It is rather the poorly designed lens cap and the failure to black out all interior objects in the cabinet which causes ambient lighting to light up the bottom of the cabinet. The hot spot is centered because that is where the lens is aimed and that is where the primary light is leaking around the first flat reflective mirror.
Also, there are no lasers shooting around inside the cabinet, or firing from the lens. There is a picture projected from the lens just like any projector. Place a sheet a paper in front of the lens and you see the picture. I have no idea how the picture goes from being laser created to an output light source.Poorly designed light filter cap degrades LaserVue picture
If you are considering purchasing a Laservue now that they are back in production, you may want to run this test first. Assuming the most expensive TV is being exhibited in an isolated room in the store; close the door and turn off the lights.
Turn off the DVD or DirecTV device and view the LaserVue without a signal source.
The screen will glow with light from the engine below.
Now decide if you can live with it, because that light is always there and it will interfere with dark scenes, especially dark scenes at the bottom center of the screen.Why is this happening?
There is plastic lens cap that encloses the lens at the bottom of the television. The lens aims the picture at a small rectangular mirror (mirror #1) which then reflects the image on to the crazy shaped parabolic mirror (mirror #2) which then reflects the image on to the big screen.
The lens cap is designed to prevent excess light from escaping from the lens and filling the interior of the cabinet.
Unfortunately, it does not work.
There is a fine line between the image edge and excess light which slips past mirror #1 and hits the front wall of the cabinet. The cap opening is about 1/16" to 3/32" to big on all sides. Furthermore some of the hardware inside the cabinet has not been blacked out. Shiny metal reflects the light adding to the ambient light inside the cabinet.The problem can be fixed to some extent.
Using black electrical tape, I successfully stopped light from hitting the front of the cabinet. Thus the only ambient light being generated was from the lens itself and mirror #2. The picture quality greatly improved so much so that the ambient light was not distracting.
The downside is that the tape has to be so carefully located so as to not create a dark area on the screen or effect the picture in other unpleasant ways. I have not as yet been able to locate the tape appropriately or come up with a better solution for shrinking down the size of the opening. As you can see in the photo, the cap has curved surfaces. I can only see molding my own cap from scratch as a solution.
The included pictures should fully illustrate what I have explained. I find it very unfortunate that Mitsubishi has chosen to accept the results of a poorly designed $.50 cent plastic cap which clearly degrades an otherwise stellar picture.