초록 ▼

A scanner including a plastic focusing lens and thermal compensation element, integrally formed with the asphere or comprising a separate element, to replace the existing glass laser diode focusing lens. The combined optical system is thereby configured to provide overall temperature compensation fo

A scanner including a plastic focusing lens and thermal compensation element, integrally formed with the asphere or comprising a separate element, to replace the existing glass laser diode focusing lens. The combined optical system is thereby configured to provide overall temperature compensation for the system with reduced cost and improved performance.

대표청구항 ▼

[ I claim:] [11.] A laser bar code scanner comprisinga light source generating a laser beam along an outgoing light path;a scanning mechanism disposed in the outgoing light path for scanning the laser beam over a scan angle to generate at least one scan line;a focusing lens positioned in the outgoin

[ I claim:] [11.] A laser bar code scanner comprisinga light source generating a laser beam along an outgoing light path;a scanning mechanism disposed in the outgoing light path for scanning the laser beam over a scan angle to generate at least one scan line;a focusing lens positioned in the outgoing light path between the scanning mechanism and the light source for focusing the laser beam, the focusing lens comprising a hybrid optical element including a refractive portion and a diffractive portion, the diffractive portion having defined thermal optical characteristics for compensating for shift in focal length of the laser beam due to thermal expansion of the focusing lens.