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A 1951 USAF resolution test chart is a microscopic optical resolution test device originally defined by the U.S. Air Force MIL-STD-150A standard of 1951. The design provides numerous small target shapes exhibiting a stepped assortment of precise spatial frequency specimens.
A barcode reader or barcode scanner is an optical scanner that can read printed barcodes and send the data they contain to computer. [1] Like a flatbed scanner , it consists of a light source, a lens, and a light sensor for translating optical impulses into electrical signals.
The RMA 1946 Resolution Chart was transmitted by NTS and NOS in the Netherlands, SRG SSR in Switzerland, [18] VRT and RTBF in Belgium, RTP in Portugal, TVP in Poland, TVB in Hong Kong, [citation needed] Venevisión in Venezuela (525-lines variant; in conjunction with Indian-head test pattern), [citation needed] WISN-TV in Milwaukee, Wisconsin (525-lines variant) [19] and on low-powered ...
The first mark sense scanner was the IBM 805 Test Scoring Machine; this read marks by sensing the electrical conductivity of graphite pencil lead using pairs of wire brushes that scanned the page. In the 1930s, Richard Warren at IBM experimented with optical mark sense systems for test scoring, as documented in US Patents 2,150,256 (filed in ...
This 5 bar resolution test chart is often used for evaluation of microfilm systems and scanners. It is convenient for a 1:1 range (typically covering 1-18 cycles/mm) and is marked directly in cycles/mm. Details can be found in ISO-3334.
The following other wikis use this file: Usage on be-tarask.wikipedia.org Відэа; Usage on cs.wikipedia.org Televizní zkušební obrazec; Usage on fr.wikipedia.org
As of 2009, a high-end flatbed scanner can scan up to 5400 ppi and drum scanners have an optical resolution of between 3000 and 24000 ppi. Effective resolution refers to the true resolution of a scanner, and is determined by using a resolution test chart. The effective resolution of most all consumer flatbed scanners is considerably lower than ...
The barcode scheme does not contain a check digit (in contrast to—for instance—Code 128), but it can be considered self-checking on the grounds that a single erroneously interpreted bar cannot generate another valid character. Possibly the most serious drawback of Code 39 is its low data density: It requires more space to encode data in ...