Kaip veikia lazeriniai delniniai brūkšninių kodų skaitytuvai

Lazerinis rankinis skaitytuvas yra vienos{0}}linijos skaitytuvas, kuriame kaip šviesos šaltinis naudojamas lazerinis diodas. Jis daugiausia yra dviejų tipų: besisukančio veidrodžio tipo ir suskaidyto veidrodžio tipo.

The representative brand of the rotating mirror type is ACAN 8500, which uses a high-speed motor to drive a prism group to rotate, so that the single-point laser emitted by the diode becomes a line. This laser line scans the bar code itself. The black bar code absorbs most of the laser light, and the white light reflects most of the laser light. At the same time, the reflected light passes through the optical lens in the "engine" and is reflected and focused on a phototransistor. Observe and scan in the time domain. Go to the black band of the barcode and output the low level of the photo-laser. When the white band is on, the photo-transistor is high. After several magnifications, the shape is a rectangular wave, which corresponds to the scanned barcode. The resulting waveform is then passed to the "decoder" section via the data line. The "decoder" is actually a single-chip microcomputer, which mainly depends on the interrupt and the single-chip computer counter to record the waveform jump time. The acquired sequence is digitally decoded during the next scan or retrace, and mainly depends on the time ratio of these counters to decode the corresponding In practical applications, there are many types of barcodes, and they need to encounter irregularities such as blister packaging folds, so the decoding part needs a certain degree of fault tolerance, but it cannot generate error codes. At present, the decoder microcontroller is generally divided into 8-bit and 32-bit. The advantage of 8-bit lies in the price and the speed of 32-bit. The laser bar code market is a mixed bag and has followed in the footsteps of ccd scanners. The price has repeatedly fallen and the cottage is rampant. However, there are several domestic manufacturers with strong capabilities. Consumers need to carefully consider what brand to use and choose the most suitable one.

Drebančio veidrodžio tipo gamybos sąnaudos yra mažesnės nei sukamojo veidrodžio tipo, tačiau lazeriniu pistoletu su šiuo principu nėra lengva padidinti nuskaitymo greitį, kuris paprastai yra 33 kartus per sekundę. Atskiri modeliai, tokie kaip OPTICON, gali pasiekti 100 kartų per sekundę. Tipiški prekių ženklai yra Symbol, PSC ir OPTICON. Labiausiai reprezentatyvus yra SYMBOL 2208.

Renkantis lazerinį skaitytuvą komercinėms įmonėms, svarbiausia atkreipti dėmesį į nuskaitymo greitį ir skiriamąją gebą, o lauko gylis nėra pagrindinis veiksnys. Nes padidinus lauko gylį, skiriamoji geba labai sumažės. Puikus rankinis lazerinis skaitytuvas turi turėti didelį nuskaitymo greitį ir didelę skiriamąją gebą fiksuotame lauko gylyje.