From: Robert E. Webber Subject: Re: Liquid Crystal displays Date: Fri, 25 Jan 91 17:27:38 EST The following summary message showed up last night in sci.optics. The comment at the end seems to indicate that there is perhaps already a VR product using this technology. As people talk about `fiberscopes,' issues seem to be confused by whether one is viewing the fibers as transferring the image `directly' or whether it is being used to transfer a camera processed signal. Also, it is unclear whether the `fiberscopes' are intended to flex during operation or not. The technical discussion outside this message seems to either involve a camera or rigid periscope arrangements. Also, it is unclear, but seems indicated, that there are significant resolution problems in this technology, i.e., one might not manage to do better than the spatial resolution of current LCD approach. --- BOB (webber@csd.uwo.ca) Message follows: >From nivek@rover.ri.cmu.edu (Kevin Dowling) Thu Jan 24 16:04:25 1991 Path: aramis.rutgers.edu!rutgers!rochester!pt.cs.cmu.edu!rover.ri.cmu.edu!nivek From: nivek@rover.ri.cmu.edu (Kevin Dowling) Subject: fiberscopes Message-ID: <11664@pt.cs.cmu.edu> Date: 24 Jan 91 21:04:25 GMT Organization: Carnegie-Mellon University, CS/RI Lines: 38 I received some replies questioning the single fiber transmitting an image (optically) that I had posted - I was wrong to say that it should have been small, single bundle of fibers. Here are some commercial examples: Mitsubishi's Diaguide scopes can be very long up to 100m or so. They are fused bundles of silica fibers, so the image is not limited to the pixels provided by mere bundles. This also eliminates the 'dark spot' problem with the mechanically bundled fiberscopes where some individual fibers break with high-flexing. There are several examples of products that pack 80,000 or more fibers into a rugged 12 mm outside diam bundle. Reichert-Jung in Southbridge MA makes a number of fiberscopes that fit this description, including right angle viewing attachments and camera adapters etc. Olympus also make a line of fiberscopes. Field of view can be up to 80 degrees on fiberscope units. Some even have panoramic views up to 140 degrees. Another neat but different idea is the Welch-Allyn device. Welch-Allyn video probe division uses a small electrical connection to a CCD chip and transmit the image in this manner. They claim it avoids the dark spots that occur in fiber bundles than have individual broken fibers (315) 685-8351 For some applications there exists some extremely small high-res color cameras - Circon Acmi and Panasonic both make units that are small and high quality cameras. Some replies I got were from people interested in Virtual Reality Applications - Concept Vision Systems in Conway WA has a fiber-based heads-up display - a large number of fibers form the image directly in front of the eyes. nivek aka : Kevin Dowling net : nivek@rover.ri.cmu.edu Robotics Institute tel : (412) 268-8830 Carnegie Mellon University Pittsburgh, PA 15213