Based on from our previous experience and evaluation as a projection screen manufacturer, we started thinking that we should have had convincing numerical criteria for evaluation other than peak gain. We also added the characteristics of wrinkle and daylight factors (see the figures below) to the performance evaluation of projection screens so that we could calculate and estimate the conditions of projection under certain environments for projection based on the criteria for evaluation.
For a long time, we had problems about white projection screens, which were lowest in prices, in terms of their yield rates and flatness. From around 1988, our material fabricators had been seriously troubled with defects such as wrinkles and creases caused by dyed and shaken cotton cloth. Materials that are commonly called "hand-woven embossed materials" also had problems of *moire patterns (interference patterns) when used with liquid crystal projectors, and needed to be improved.
To balance the prices and flatness of projection screens, we started developing and producing new white matte projection screens #WG-148TR. Because they have properties different from those of cotton materials, inquiries and complaints were continuously received at the factory for a while. In-house complaints were also continuously received and productivity was not improved because workers at the factory were uncomfortable with handling polyvinyl chloride sheets used for the front and back sides of screens due to lack of smoothness during processing.
However, from around this time, our firm started to be convinced that white projection screens are the basics for our products. In January 1998, during an interview with us, a critic "F" publicly reconfirmed in a professional magazine called HiVi, "Expensiveness does not always ensure functions and quality. Expensive projection screens do not necessarily mean good projection screens. White screens are essential."
But we have a long way to go to reach ideal projection screens. Though we admitted that white screens were essential, our white screens were not improved because of a shift to digital projection software and the continued problems of *moire patterns (interference patterns). At that time, we really felt that, at any rate, we should make many different tries.
*moire patterns (interference patterns):The noise which the unevenness of a screen side and the pixel of a liquid crystal projector interfere in the fine hole of embossing on the surface of a screen, or a sound screen etc., and is generated
