| 摘要 |
<p>Dual-focus optical scanner for scanning an object, provided with optical illuminating means for illuminating the object to be scanned with a light point derived from a light source, which illuminating means have their own optics, and with optical imaging means for imaging the object onto a point sensor, which imaging means have their own optics. Said illuminating means and said imaging means are embodied in a coaxial relation with substantially coincident optical axes. The focal plane of the illuminating optics and the focal plane of the imaging optics in the object area are slightly spaced, the separation of said two spaced focal planes being such that the working range of the scanner is the sum of the depths of field of the illuminating and imaging optics, defined according to required spatial resolution. Said optical scanner can be used as a wandtype symbol code reader, such as a bar code reader, for reading the symbol code by relative manual scan movement. The reader includes at least one lens or lens-set (5), and in the optical path of the illuminating means a deflection member (4) is positioned between the one lens or lens-set (5) and the light source (1) for de-flecting the light, scattered from the symbol code, onto the sensor (9). <IMAGE></p> |
