GBvi is a UK-based company that has developed a very nice niche in the simulation market – optical edge-blending technology. (GBVI Gets Good References) Edge blending is needed when multiple projectors are used to create one seamless image. If the content is bright enough, electronic edge blending can be done by simply ramping down the brightness in the blend zone in the video signal. But for darker simulation scenarios, optical edge blending is needed to lower the combined brightness in the overlap zone. Optical edge blending means design a physical aperture to place in front of the projector to reduce light in the blend zone to much lower levels than can be achieved with electronic blending.
At Display Summit last October, founder George Blackham gave a very nice presentation describing the many ways one can design optical edge blending plates along with all the pros and cons. We had no idea there were so many options – and trade-offs. (DS02 Summary of the Components and Vis/Sim Session at Display Summit 2017)
It I/ITSEC, GBvi showed two new technologies in its Chronos range; the Chronos Greyscale and Chronos Rewind. Chronos Greyscale is a new optical blend technology that addresses the small 4K and 8K class of projection systems where some optical trade-offs are most challenging, particularly with laser-phosphor illumination. It turns out that one design choice is to fabricate a series of small holes at the blend edge to gradually reduce light from a clear to an opaque region. But with laser-phosphor engines, the narrow band light can start to cause diffraction effects with these features, comprising the integrity of the blend region.
Chronos Greyscale implements a changing grayscale over the blend zone using a specially developed process and materials which must withstand very high optical flux levels without any distortions or movements. Variable density masks can be fabricated in any shape to provide a proper blend zone.
The company’s primary blending solution, Chronos Glass, can be enhanced with Greyscale technology.
Chronos Rewind addresses the issue of complexities that arise when using Auto-Alignment (AA) systems for projection display calibration. According to the company, Chronos Rewind uses an actuated platform and simple trigger interface to move the blend mask to and from the projector lens as required in a carefully controlled and precise manner.
GBvi works with partners including Immersive Display Solutions and Antycip Simulation, the latter uses GBvi technologies in fast-jet and helicopter simulation applications. – CC
