Have you ever noticed something a bit off when using a laser projector with some projection screens? In the following article, Draper AV Consultant Relations Manager Steve Cook addresses concerns over laser projection, and outlines what screens work best.
There have been many questions in the AV industry about the laser technology used in some projectors, and what screen surfaces are best used with them. Unfortunately, those questions have led to some misinformation. This document will try to clear up any confusion.
Laser technology is implemented in both LCD and DLP projectors in various ways. When designing a projection system, you should know which type you will be using, and which projector types have issues with certain screen surfaces.
Below are the various type of laser technology projectors:
- Laser Phosphor Technology based on 3LCD Panel Technology (blue laser)
- Laser Phosphor Technology based on 1-chip DLP Technology (blue laser)
- Laser Phosphor Technology based on 3-chip DLP Technology (blue laser)
- RB Laser Technology based on 3-chip DLP Technology (red and blue laser)
- RGB Laser Light Source with 3-chip DLP Technology (red, green & blue laser)
- Hybrid Light Source (blue laser)
Laser technology is just another type of light source used in projectors. This type of light source lasts longer than lamp-based light sources. However, lasers exhibit something called “speckle.” Speckle occurs when a laser light source is projected onto a surface and there is a ring of artifacts around the primary spot from the light beam.
Projectors use red, green, and blue lasers in various ways, sometimes along with other types of light sources and color filtering.
- Projectors with blue laser only do not have any visible speckle used with any Draper screen surfaces. The wavelength of the blue lasers does not have visible speckle at the screen surface. Projectors of this type are the majority of the affordable models used in most applications.
- Projectors with an RB laser light source with 3-chip DLP do not have any visible speckle used with any Draper screen surfaces. The wavelengths of the red and blue lasers do not have visible speckle at the screen surface.
- Projectors with an RGB laser light source with 3-chip DLP technology do have visible speckle at the screen surface. This speckle is created by the green laser. The wavelength of the green laser is visible on all screen surfaces, more so with surfaces that have higher gain or ambient light rejecting properties that are higher in specular reflectivity than matte surfaces. Not all manufacturers use green lasers. The best option for a screen surface to use with this type of technology is a premium matte surface like Draper TecVision XT1000X White for dark spaces, or TecVision XH700X Grey for spaces with controlled light.
Planning your next projection system? Contact your Draper projection experts for the perfect screen in your application and viewing conditions!
