Coating Solutions

Glass Products


Glass Fabrication


How does a Front Surface
Mirror help a Rear Projection System?

Rear projection systems ideally use a front surface mirror (or first surface mirror) instead of a second surface mirror for image clarity.


Image clarity is often determined by taking into account two primary indicators. Amount of ghosting is the first and is a condition where an image is displayed two or more times with the secondary images being offset on the display. The secondary images typically have a decreased intensity. In the case of the use of a second surface mirror the ghosting images are at about one tenth of the intensity of the primary image when the angle of incidence is around 65 degrees.


The second indicator is contrast. This is measured as the minimum light intensity level in the image subtracted from the maximum light intensity level. This is then divided by the maximum light intensity level added to the minimum light intensity level. In essence this means that a projected image with an effective minimum light intensity level of zero and a maximum light intensity level higher than zero will have a contrast ratio of one. As the minimum intensity level becomes brighter, the image’s contrast level decreases and the overall picture quality decreases. If the minimum and maximum levels are the same value, then the contrast is zero and the image will look washed out.


With a first surface mirror, only the aluminum surface on the front of the mirror reflects the incident light. This means that any ghosting produced by the mirror is entirely eliminated and the contrast ratio of the incident light is unaffected by the reflecting surface.


For more information about first surface mirrors and their benefits in rear projection systems please call 800.426.2864 or email us.


Abrisa Technologies is a recognized global supplier of high quality, fabricated glass components, optical thin film coatings, and custom glass solutions for a wide variety of industries. From our US based Abrisa Industrial Glass fabrication facility in Santa Paula, CA and our ZC&R Coatings for Optics division in Torrance, CA we serve diverse industries such as microelectronics and displays, semiconductor, military, automotive, aerospace, medical, biomedical and scientific R&D. We provide custom specialty flat glass and coating products for applications such as: flat panel display, touch and gesture recognition; visible to IR imaging and surveillance; entertainment, indoor and outdoor lighting; advanced instrumentation; and photonics.


Need information for Glass Substrates & Fabrication - Contact us Toll Free at: (877) 622-7472 or

Need information for Thin Film Optical Coatings - Contact us Toll Free at: (800) 426-2864 or

Home | About Us | Markets & Applications | Products & Services | News & Events | Contact Us
Terms of Use | Privacy Policy | Site Map | Terms of Sale | Send Comments About this Site to: Abrisa Technologies Webmaster © 2010 Abrisa Technologies All Rights Reserved