Molded code mark reader with elongated read beam

Claim 3

A method as defined in claim 1 for detecting essentially hemispherical code marks, wherein the substantially collimated light beam has an essentially rectangular cross-sectional area and is positioned to illuminate said sector over an essentially rectangular area.

Claim 4

A method as defined in claim 2, where the area of illumination on the vessel has a vertical dimension greater than the diameter of the code marks, and a width less than said diameter.

Claim 5

A method as defined in claim 1, wherein the vessel comprises a substantially radially symmetric transparent container, and the code marks are located in a circumferential band near the base of the transparent container.

Claim 6

A method as defined in claim 1, wherein the sector comprises an inclined band near a base of the vessel.

Claim 7

A method as defined in claim 1, wherein the detecting step comprises the step of detecting light reflected from an individual code mark which passes through an approximately circular region having an axis approximately aimed at said code mark during the illumination of said code mark.

Claim 8

Apparatus for reading molded code marks circumferentially arranged about a cylindrical sidewall of a container, said apparatus comprising: means for rotating the container to sequentially position said marks for reading; means for illuminating the code marks during rotation of the container with a substantially collimated light beam of elongated cross-section, said light beam having a height substantially greater than the height of said code marks to accommodate vertical misalignment and a width less than or equal to the horizontal separation of adjacent code marks; lens means for collecting light transmitted from an area of the surface of said container substantially broader than that of a molded code mark; and photodetector means for producing light intensity signals representative of the intensity of the light collected by said lens means; wherein, in the absence of a code mark in the path of said collimated light beam, the container reflects the light beam away from said lens means so that said photodetector means produces a light intensity signal corresponding to the absence of a code mark, and in the presence of a code mark in the path of the light beam, the code mark reflects a detectable portion of said light beam to said lens means so that said photodetector means produces a light intensity signal corresponding to the presence of said code mark.

Claim 9

Apparatus for reading molded code marks circumferentially arranged about a cylindrical sidewall of a container, said apparatus comprising: means for rotating the container to sequentially position said marks for reading; means for illuminating the code marks during rotation of the container with a substantially collimated light beam of elongated cross-section, said light beam having a height substantially greater than the height of said code marks to accommodate vertical misalignment and a width less than or equal to the horizontal separation of adjacent code marks; lens means for collecting light transmitted from an area of the surface of said container substantially broader than that of a molded code mark; and photodetector means for producing light intensity signals representative of the intensity of the light collected by said lens means; wherein, in the absence of a code mark in the path of said collimated light beam, the container reflects the light beam away from said lens means so that said photodetector means produces a light intensity signal corresponding to the absence of a code mark, and in the presence of a code mark in the path of the light beam, the code mark reflects a detectable portion of said light beam to said lens means so that said photodetector means produces a light intensity signal corresponding to the presence of said code mark.

Claim 10

Apparatus as defined in claim 7, further comprising means for causing the illumination means and the photodetector means to scan said sector for code marks one at a time, and signal processing means for processing said light intensty signals over time and producing code identification signals corresponding to said light intensity signals and representative of a code formed by said code marks.

Claim 11

Apparatus as defined in claim 7 wherein the illuminating means includes means for limiting the cross-sectional width to less than a spacing between the code marks, and means for orienting the light beam so that it illuminates no more than one code mark at any time.

Claim 12

Apparatus as defined in claim 7, wherein the illuminating means includes a light source periodically varying at a high frequency, and the signal processing means includes demodulator means for extracting said light intensity signals at said high frequency.

Claim 13

Apparatus as defined in claim 7, wherein the lens means comprises an objective lens and a field lens, said objective lens being positioned to receive light from said container and focus the light upon said field lens, and said field lens being positioned to focus the light focused upon it by said objective lens onto the photodetector means.

Claim 14

Apparatus as defined in claim 7 wherein the portion of light collected by said lens means passes through a cylindrical region having an axis sequentially aimed at said code marks during the rotation of the container.

Claim 15

An apparatus as defined in claim 7 wherein said means for illuminating the container includes a source of light and two plano-cylindrical lenses oriented perpendicularly relative to each other and placed between the source of light and the container to limit the cross section of the light beam.

Claim 16

A method as defined in claim 1 wherein the illuminating step comprises the step of passing light through a pair of plano-cylindrical lenses oriented perpendicular to each other to collimate the light.

Claim 17

Apparatus for reading raised dot code marks circumferentially arranged about a sector of a cylindrical sidewall of a container, said apparatus comprising: means for rotating the container to sequentially position the code marks for identification; means for illuminating the container during rotation at said sector with a substantially collimated light beam of elongated cross-section, said light beam having a cross-sectional width exhibited on the sidewall of said container which is approximately equal to or less than a spacing between the code marks and a cross-sectional height substantially greater than the diameter of said code marks to accommodate misalignment, and being oriented relative to the code marks such that the light beam can illuminate no more than one code mark at any one time, said light beam being reflected from said container; and photodetector means, for collecting light transmitted from a portion of the surface of said container encompassing but substantially broader than the area illuminated by the substantially collimated light beam and for producing an output signal representative of the intensity of collected light, wherein such transmitted light includes a detectable portion of any reflections of said light beam from the code marks but substantially none of the reflections of said light beam from other portions of the container.

Claim 18

Apparatus for reading raised dot code marks circumferentially arranged about a sector of a cylindrical sidewall of a container, said apparatus comprising: means for rotating the container to sequentially position the code marks for identification; means for illuminating the container during rotation at said sector with a substantially collimated light beam of elongated cross-section, said light beam having a cross-sectional width exhibited on the sidewall of said container which is approximately equal to or less than a spacing between the code marks and a cross-sectional height substantially greater than the diameter of said code marks to accommodate misalignment, and being oriented relative to the code marks such that the light beam can illuminate no more than one code mark at any one time, said light beam being reflected from said container; and photodetector means, for collecting light transmitted from a portion of the surface of said container encompassing but substantially broader than the area illuminated by the substantially collimated light beam and for producing an output signal representative of the intensity of collected light, wherein such transmitted light includes a detectable portion of any reflections of said light beam from the code marks but substantially none of the reflections of said light beam from other portions of the container.

Claim 19

An apparatus as defined in claim 15 wherein said means for illuminating the container includes a source of light, and two plano-cylindrical lenses oriented perpendicularly relative to each other and supported between the source of light and the container to limit the cross-section of the light beam.