Must Knows about Fresnel Ambient Light Rejection Projector

When it comes to projector, contrast is key to for a projector to please our eyes.

It is all about how dark is the dark.

Ambient Light is the enemy of a projector.  Ambient light scattered by a screen enters our eye with the projector light reduces the contrast.  The key is to reduce the ambient light entering eye.

Fresnel Optical Structure 

The core element in Fresnel screens is the Fresnel lens. The Fresnel is made up from thousands of concentric lenses – each with its own unique profile. Barely visible to the naked eye, these lenses form a circular pattern from the screen center and outwards – like ripples in a pond.

With Fresnel screen, only light from the projector will be focused and ambient lights from both sides and top of the screen will be rejected.

The Fresnel screen can efficiently reject over 85% of the ambient light which makes the image vivid and bright under ambient light.

The core component of the Fresnel screen is a film that made of 8 layers: scratch resistant layer, color layer, diffusion layer, cylindrical lens layer, speckle suppression layer, Fresnel Lens layer, reflecting layer and black coating layer. 

Ultrashort Throw and Long Throw

By designing different Fresnel patterns, the screen can entertain ultrashort throw (laser TV) and long throw projector. For ultrashort throw, the film needs to have ultra flat supporting substrate, and this makes it expensive compared to long throw version as its more tolerant to the flatness of the supporting substrate. 

Tradeoff between gain and view angle 

By designing different Fresnel patterns, the screen can trade gain versus view angle. By focusing more lights into a narrow view angle, we achieve a high gain screen.

Normally, we have gain of 1.2 and view angle of 160 degree, and gain of 1.8 and view angle of 80 degree. Generally speaking, a large view angle is more expensive.

For better experience, a projector with more than 500 lumens is recommended. As the effect of the screen for a lower lumens will not be that obvious.

Form factors

The active component is the fresnel film. It can be installed on a string frame on a fabric like LinkSprite offers or attached on a rollable frame.

Experience the difference