AVS Addicted Member
Join Date: Dec 2000
Location: brookeville, maryland, usa
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 907 Post(s)
All this laser talk. JVC did not invent the laser lit spinning yellow phosphor wheel. Its more or less an off the shelf light source than any manufacturer can license/procure.
It uses a low powered lase to generate the blue primary and to make a spinning yellow phosphor wheel give off a bright yellow light. Except for the blue direct light which is tiny compared to the green and red light a projector gives out, the laser lit phosphor is just like any traditional light source in that diachromatic filters, wire grid polarizers etc etc are used to extract the red and green primaries from the light and to polarize that light so that liquid crystals can modulate it.
speckle is not an issue because except for the blue light, laser light does not hit the screen. The industry is and will be marketing these machines as lasers. That is almost utter bull. The laser is a phosphor ignitor, that is all except for the blue. JVC solved the speckle problem, Sure they didn't. Speckle is an artifact of laser light hitting a screen. get rid of the laser beam and the artifact disappears. solve it, no they abandoned true lasers, perhaps for very good reasons the least of which are costs and regulatory issues. A spinning phosphor wheel can put out a lot of light and if designed and operated correctly using certain design tricks can last far longer than any bulb. Obviously the power of the small blue laser can be varied. For more light, use a more powerful blue laser. Oh oh. This is where regulatory issues can rear their ugly head. One manufacture may stay within the class 2 laser power limits while another trying to put out 5000 lumens may exceed class 2.
Bulbs for many projectors will eventually be replaced by blue laser spinning phosphor engines. almost all the manufacturers will be adopting this. NEC, Sony, JVC, Epson. the start wil be this year in HT land. Cheap projectors will continue to use bulbs.
call me at: 240 876 2536