New Graflex RB Super D 4x5 camera Fresnel lens / Ground glass

  
Graflex R B Super D 4x5 camera. This Fresnel screen/ground glass significantly increase the brightness of the image on the ground glass to make focusing much more easier and accurate. This Fresnel/ground can be also used with Graflex 4x5 RB Series cameras. The condition is unconditionally guaranteed. About modern Optical Acrylic Ground Glass. Nowadays all of eyeglasses are made of the plastic acrylic. In the currently market, one definitely cannot find a modern eyeglasses which are made of traditional acid glass. Because the modern optical acrylic is much more lighter, brighter, stronger and durable that the traditional acid one.

The new type ground glass made of optical anti-scratch acrylic is much more brighter and stronger that the original acid ground glass. We are professional provider of the large format items including ground glass and fresnel lens. Please see visit our website for more details. The Fresnel lens was invented by French physicist Augustine Fresnel, the Augustin Fresnel first used this lens design to build a glass Fresnel lens - lighthouse lens in 1822.

The Fresnel lens is a thin, flat optical lens which consists of a series of small narrow concentric grooves on the surface of a lightweight plastic sheet in order to reduce the thickness, weight and cost. Each groove is at a slightly different angle than the next and with the same focal length in order to focus the light toward a central focal point. Every groove can be considered as an individual small lens to bend parallel Fresnel light waves and focus the light. The lens actually eliminates some spherical aberration.