초록 ▼

A bar code reader head having an optical block with cavities formed therein into which various optical elements may be placed without the need for any adjustment thereof. A first illumination source, producing any desired spectrum of light, illuminates at least a portion of the bar code. A second il

A bar code reader head having an optical block with cavities formed therein into which various optical elements may be placed without the need for any adjustment thereof. A first illumination source, producing any desired spectrum of light, illuminates at least a portion of the bar code. A second illumination source may be provided to produce a second spectrum of light. Reflected light passes through a lens in front of which is an aperture slit parallel to the bar code bars. A channel is formed between the lens and a photodetector perpendicular to the light path. If both visible and infrared illumination sources are used, visible light is focused at the side of the channel toward the lens and infrared light is focused at the other side of the channel. In the channel is a template having at least one discriminator slit parallel with the slit in front of the lens. The width of the discriminator slit depends upon the widths of the bars to be read. With visible light, the template is positioned with the slit at the side toward the lens. With infrared light, the template is positioned with the slit at the other side. Alternatively, a specially designed lens may be employed to focus both visible and infrared light at one side of the channel. The template may have additional slits for changing the resolution of the device by moving the template to align a slit having a different width with the light path, thus allowing use of the device with different bar codes having substantially different bar widths.

대표청구항 ▼

A bar code reader head, comprising: (a) a body; (b) a first illuminating source producing a first spectrum of light wavelengths disposed within said body so as to illuminate at least a portion of a bar code; (c) a first lens disposed within said body to focus said first spectrum of light wavelengths

A bar code reader head, comprising: (a) a body; (b) a first illuminating source producing a first spectrum of light wavelengths disposed within said body so as to illuminate at least a portion of a bar code; (c) a first lens disposed within said body to focus said first spectrum of light wavelengths reflected from said bar code, said reflected light being focused at a first focusing plane within said body distant from said first lens; (d) detector means disposed within said body on the side of said first focusing plane opposite said first lens to detect light focused by said first lens; and (e) discriminator means disposed within said body and placed at said first focusing plane, such as to limit the width of said bar code which can be seen by said detector means.