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Opaque Projector
Opaque projectors are the predecessor to the overhead projector. They display opaque materials by shining a bright lamp, usually limelight, onto the object from above. A system of mirrors, prisms and/or imaging lenses is used to focus an image of the material onto a viewing screen. As they must project the reflected light, opaque projectors require brighter bulbs and larger lenses than overhead projectors. Care must be taken that the materials are not damaged by the heat generated by the light source. An opaque projector is typically used to project images of book pages, drawings, mineral specimens, leaves, etc. They have been produced and marketed as artists’ enlargement tools to allow images to be transferred to surfaces such as prepared canvas, or for lectures and discourses. In the early and middle parts of the 20th century, low-cost opaque projectors were produced and marketed as toys for children. In educational settings, the specific role of the opaque projector has been superseded by the ‘presenter’, a lighted table with a fixed video camera above it. The image from the camera is displayed using a separate projector. The desktop presenter unit is sometimes called an opaque projector. The .Opaque projector was designed and manufactured by the American Optical Company starting in the early 1960s. The opaque and overhead projector product lines were sold to Kalart Victor in the mid 70s and then sold again to Neumade in the 80s. Neumade continues to manufacture the American optical opaque projector with the same parts that were used in the original American Optical units. An original opaque projector is the Beseler opaque projector; you can buy many second hand Beseler opaque projectors on eBay at very reasonable prices. There are many advantages in buying a used opaque projector. You can save a considerable amount of money and still have a perfect opaque projector. Just be sure to check the seller’s feedback before you part with your money. You should also use an opaque projector comparison website; this will compare hundreds of opaque projectors within seconds, saving you a lot of hard work and time. Once you have bought your opaque projector, you should take the time to write a review about it, this will assist other people that are thinking of buying an opaque projector. Some people don’t have a clue when it comes to opaque projectors and your review could really be beneficial to them.
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