A person with low myopia must NEVER use glasses for near work. If you take off your glasses you'll do a good thing for your eyes. If you really have to do a lot of reading work at very short distance, such as reading a book (usually 30 or 40 ... more

by David Stork ABSTRACT: David Hockney has recently hypothesized that some early Renaissance painters employed optical devices such as concave mirrors to project images of a scene or part of a scene onto their supports, which they then traced or ... more

• One of the urgently needed improvements is to include a visual display and/or aural reading of HOW the ballot marked and submitted is being read before actually counting them electronically. If one cannot trust what is touched and confirmed on ... more

For stable chopping with minimum jitter and drift, the Model 3501 optical chopper uses precision photo-etched wheels mounted on a high-quality DC motor. In addition, the chopper controller has its own internal crystal-controlled frequency ... more

For an optical complex spectrum analysis with the AP2440A, two conditions have to be met : • The number of bits of the repeated pattern have to be a power of 2 (2, 4, 8, 16, 32, ....) • The pattern -repeat- frequency (pattern frequency = bit rate / ... more

Red Tray Optical is owned by Jerry Hayes, OD, the founder of Hayes Marketing, HMI Buying Group and e-dr. Red Tray employs an extremely knowledgeable staff that averages 17 years experience in the wholesale optical industry. Click here to read more... ... more

On DRE machines, the voter indicates his or her vote, either by using an ATM-style touch screen, pressing buttons, or turning dials on a computer device. Optical scanners use paper ballots that voters mark (or, in some cases, a machine generates) ... more

As part of its unique formula, Purosol Optical neutralizes the molecular charges on the lens surface, which normally attracts dust and dirt particles, thereby extending the life of the cleaning. While this effect diminishes over time, the particles ... more

There are many factors that affects the prolong usage of an optical disc. The following are some information on the conditions of storage for optical disc. • Reduce exposure of light (sunlight) The exposure of sunlight causes heat build-up in the ... more

Optical fiber fusion splicing is a welded joint formed between two optical fibers. It is a permanent, low-loss, high-strength joint compared with other temporary joint such as a mechanical splice. Optical fiber fusion splices play a crucial role in ... more