Bar code reading devices

Claim 2

Apparatus as claimed in claim 1, wherein the said scanning beam forming means (1, 2) and the said additional beam-forming means include first and second sets of mirrors (21A, 21B) arranged respectively for deflecting the light of the first and second optical beams towards the said article.

Claim 3

Apparatus as claimed in claim 1 or 2, including control means operable to interrupt production of the said first and second optical beams alternately.

Claim 4

Apparatus as claimed in claim 1, 2 or 3, wherein the said additional beam-forming means comprises a second light source (3B), for providing the said further light.

Claim 5

Apparatus as claimed in claim 1, 2 or 3, including a beam splitting device (S) arranged to split light from the said light source (3S) so as to provide the light for the said first optical beam and also the said further light.

Claim 6

Apparatus as claimed in claim 1, 2, 4 or 5, wherein the said movable light-deflecting device (1) has respective reflecting and non-reflecting surface portions (15, 17) such that when, during movement of the device, light for forming the said first optical beam is incident on the device at a reflecting surface portion (15) thereof the said further light is incident on the device at a non-reflecting surface portion (17) thereof, and vice versa, thereby to ensure that only one of the said first and second optical beams is incident upon the said article at any one time.

Claim 7

Bar code reading apparatus for scanning a bar code symbol on a surface of an article placed in a predetermined positional relationship to the apparatus, which apparatus includes: a light source (153); scanning beam forming means (155, 156), including a movable light-deflecting device (155) arranged to receive light from the said light source, for deflecting such light so as to cause an optical beam to scan across the said symbol; and light sensor means (159, 160), arranged for receiving light reflected back from the said symbol, for providing an electrical signal responsive to the received light; characterised in that the said movable light-deflecting device (155) is a rotatable polygonal mirror having a plurality of concave reflectors (161) located at different respective angular positions around the axis (164) of rotation of that mirror, each of which reflectors has first and second planar reflecting surfaces (162, 163) that are inclined to one another and that are arranged one after the other in a direction along that axis (164) so that the line of mutual intersection of the respective planes of those surfaces is inclined to the said axis (164), a first reflector (161) of the said plurality differing from a second reflector (161) of that plurality in its angle of inclination (ϑ₂) between its first and second planar reflecting surfaces (162, 163) and/or in the angle of inclination (ϑ₁) of its said line of mutual intersection to the said axis (164), so that deflection by the said first and second reflectors (161) causes the point of incidence of the optical beam to follow first and second different linear paths across the said surface of the article when the apparatus is in use.

Claim 8

Apparatus as claimed in claim 7, wherein the said rotatable polygonal mirror forms a part of a hollow structure (175) open at one axial end thereof, internal surfaces of the structure providing the said first and second planar surfaces (172, 173) of the said reflectors (171).

Claim 9

Apparatus as claimed in claim 7 or 8, being apparatus as claimed in any one of claims 1 to 6.

Claim 10

A multi-directional bar code reading device for reading a bar code on an object that is to be read by projecting scanning beams from many directions, comprising: a plurality of mirrors (2) arranged around a beam scanning unit (1); and a plurality of beam sources (3) for emitting beams toward said beam scanning unit (1); wherein said beam scanning unit (1) is irradiated with beams generated from the plurality of beam sources (3), scanning beams are reflected by said plurality of mirrors (2) and are projected from a plurality of directions onto an object (5) to be read, and light reflected from the object (5) is detected in order to read bar codes on said object (5) to be read.

Claim 11

A multi-directional reading device according to claim 10, wherein the beam is emitted exclusively from only one of said plurality of beam sources (3).

Claim 12

A multi-directional reading device for reading an object that is to be read by projecting scanning beams having different patterns thereon, comprising: beam sources for emitting beams; a beam scanning unit which has beam reflecting surfaces and beam non-reflecting surfaces in order to form one scanning beam by reflecting, only one beam among the beams emitted from the beam sources; and mirrors corresponding to each of said beam sources in order to reflect only one scanning beam among beams formed by the beam scanning unit and to project it onto the object that is to be read; wherein said one scanning beam is projected onto the object that is to be read by any one of said mirrors.

Claim 13

A multi-directional reading device according to claim 10, 11 or 12, wherein an optical system having a spectroscope and a light source is further provided and is adapted so as to be able to function as a plurality of apparent beam sources emitted from only the one light source.

Claim 14

A multi-directional bar code reading device for reading bar codes marked on an object that is to be read by projecting scanning beams having different patterns thereon and by scanning the bar codes by means of a light beam, comprising: a light source for emitting said light beam; and a rotary polygon mirror having a plurality of reflecting portions for reflecting said light beam from said light source, wherein at least two or more reflecting planes are provided for said each reflecting portion in order to form multi-directional scanning patterns in said rotary polygon mirror.