INDICIA READING TERMINAL HAVING PLURALITY OF OPTICAL ASSEMBLIES

• US 20100133345A1
• Filed: 12/02/2008
• Published: 06/03/2010
• Est. Priority Date: 12/02/2008
• Status: Active Grant

• Current Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Original Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Inventors: Gannon, Colleen P., Feng, Chen, Havens, William H., Wang, Ynjiun P., Li, Jianhua
• Granted Patent: US 8,783,573 B2
• Time in Patent Office: Days
• US Class Current: 235/472.10
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning

Abstract

There is described an indicia reading terminal having an image sensor array including a plurality of pixels, a first optical assembly for focusing imaging light rays onto a first set of pixels of an image sensor array and a second optical assembly for focusing imaging light rays onto a second set of pixels of the image sensor array. The indicia reading terminal can be adapted to process image data corresponding to pixels of the image sensor array for attempting to decode a decodable indicia.

Claims

1. An indicia reading terminal comprising:

a two dimensional image sensor array extending along an image plane, said two dimensional image sensor array comprising a plurality of pixels;

a hand held housing encapsulating said two dimensional image sensor array;

a first optical assembly having a center optical axis and an imaging lens, said first optical assembly for focusing imaging light rays onto a first set of pixels of said two dimensional image sensor array, wherein said imaging light rays transmitted by said first optical assembly are transmitted about said center optical axis of said first optical assembly, and wherein said first optical assembly is adapted so that said center optical axis of said first optical assembly is essentially unfolded;

a second optical assembly having a center optical axis and an imaging lens, said second optical assembly for focusing imaging light rays onto a second set of pixels of said two dimensional image sensor array, wherein said imaging light rays transmitted by said second optical assembly are transmitted about said center optical axis of said second optical assembly, and wherein said second optical assembly includes an optical surface that folds said center optical axis of said second optical assembly by an angle of more than 10 degrees;

a memory capable of storing a frame of image data, said frame of image data representing light incident on said image sensor array; and

a CPU capable of addressing said memory, wherein said CPU is adapted to attempt to decode a decodable indicia represented in said frame of image data.

2. The indicia reading terminal of claim 1, wherein said imaging lens of said first optical assembly has a shorter focal length than said imaging lens of said second optical assembly.

3. The indicia reading terminal of claim 1, wherein said indicia reading terminal is adapted so that a field of view defined by said first optical assembly in combination with said image sensor array when said indicia reading terminal is at a certain terminal to target distance is larger than a field of view defined by said second optical assembly in combination with said image sensor array when said indicia reading terminal is at said certain terminal to target distance.

4. The indicia reading terminal of claim 1, wherein said first optical assembly has a shorter best focus distance than said second optical assembly.

5. The indicia reading terminal of claim 1, wherein said first optical assembly has a shorter best focus distance than said second optical assembly, wherein said first optical assembly has a shorter focal length than said second optical assembly, and wherein said first and second optical assemblies are fixed assemblies such that that said best focus distances and said focal lengths of said first and second optical assemblies are fixed.

6. The indicia reading terminal of claim 1, wherein said first set of pixels comprises a larger number of pixels than a number of pixels of said second set of pixels.

7. The indicia reading terminal of claim 1, wherein a ratio of pixels of said first set of pixels to said second set of pixels is greater than 1.5.

8. The indicia reading terminal of claim 1, wherein said second optical assembly includes a double folding prism disposed in an optical path of said second optical assembly intermediate of said imaging lens of said second optical assembly and said image sensor array, the double folding prism folding said center optical axis of said second optical assembly in at least two locations, said double folding prism being adapted so that said center optical axis of said second optical assembly extends from said image sensor array at an angle that deviates from a normal angle by less than 10 degrees.

9. The indicia reading terminal of claim 1, wherein said second optical assembly includes a double folding prism disposed in an optical path of said second optical assembly intermediate of said imaging lens of said second optical assembly and said image sensor array, the double folding prism having at least two reflective surfaces for bending said center optical axis of said second optical assembly, said double folding prism being formed utilizing one of a precision molding process and a precision grinding process.

10. The indicia reading terminal of claim 1, wherein said indicia reading terminal is capable of processing image data of said certain frame for attempting to decode a 2D bar code symbol representation, and wherein said indicia reading terminal is operative so that a level of optimization for decoding of a 2D bar code symbol representations is greater when said CPU processes image data representing light incident on said first set of pixels than when processing image data representing light incident on said second set of pixels.

11. The indicia reading terminal of claim 10, wherein said indicia reading terminal is restricted from operating according to an algorithm for attempting to decode a 2D bar code symbol when processing image data corresponding to said second set of pixels.

12. The indicia reading terminal of claim 1, wherein said first optical assembly defines with said image sensor array a first field of view, wherein said second optical assembly defines with said image sensor array a second field of view, and wherein said indicia reading terminal is adapted so that said indicia reading terminal projects an aiming pattern at a substantially fixed location in relation to said second field of view though a range of terminal to target distances ranging from a short range terminal to target distance of about 130 mm to a long range terminal to target distance of about 420 mm.

13. The indicia reading terminal of claim 1, wherein said first optical assembly defines with said image sensor array a first field of view and wherein said second optical assembly defines with said image sensor array a second field of view, and wherein said indicia reading terminal is adapted so that said indicia reading terminal projects an aiming pattern substantially at a horizontally extending centerline of said second field of view though a range of terminal to target distances ranging from a short range terminal to target distance of about 130 mm to a long range terminal to target distance of about 420 mm.

14. The indicia reading terminal of claim 1, wherein said indicia reading terminal is adapted so that said first set of pixels includes a set of pixels extending across more than 50% of the rows of said image sensor array and wherein said second set of pixels includes a set of pixels extending across less than 50% of rows of pixels of said pixels of image sensor array.

15. The indicia reading terminal of claim 1, wherein said second optical assembly includes an optical surface that folds said center optical axis of said second optical assembly by more than 30 degrees.

16. The indicia reading terminal of claim 1, wherein said indicia reading terminal includes aiming pattern generator that projects an aiming pattern substantially at a horizontally extending centerline of a field of view defined by said first optical assembly in combination with said image sensor array through a range of terminal to target distances ranging from about 130 mm to 420 mm.

17. The indicia reading terminal of claim 1, wherein said indicia reading terminal wherein said first optical assembly and said image sensor array define a first field of view, and wherein said second optical assembly and said image sensor array define a second field of view, and wherein said terminal includes a first a first aiming pattern generator and a second aiming pattern generator, the first aiming pattern generator capable of projecting an aiming pattern substantially at a horizontally extending centerline of said first field of view through a range of terminal to target distances, the second aiming pattern generator capable of projecting an aiming pattern substantially at a horizontally extending centerline of said second field of view through a range of terminal to target distances.

18. The indicia reading terminal of claim 17, wherein said terminal is operative so that at least one of said first and second aiming pattern generators is activated responsively to a sensed condition.

19. The indicia reading terminal of claim 1, wherein said first optical assembly and said image sensor array define a first field of view and wherein said second optical assembly and said image sensor array define a second field of view, and wherein said terminal includes an aiming pattern generator that projects an aiming pattern substantially at a horizontally extending centerline of said second field of view through a range of terminal to target distances.

20. An indicia reading terminal comprising:

a two dimensional image sensor array extending along an image plane, said two dimensional image sensor array comprising a plurality of pixels;

a hand held housing encapsulating said two dimensional image sensor array;

a first optical assembly defining in combination with said image sensor array a first field of view, said first optical assembly having a center optical axis and an imaging lens, the first optical assembly for focusing imaging light rays onto a first set of pixels of said two dimensional image sensor array, said first set of pixels comprising more than 50% of pixels of said image sensor array, wherein said imaging light rays transmitted by said first optical assembly are transmitted about said first center optical axis of said first optical assembly, and wherein said first optical assembly is adapted so that said first center optical axis is essentially unfolded;

a second optical assembly defining in combination with said image sensor array a second field of view, said second optical assembly having a center optical axis and an imaging lens, the second optical assembly for focusing imaging light rays onto a second set of pixels of said two dimensional image sensor array, said second set of pixels comprising less than 50% of pixels of said image sensor array, wherein said imaging light rays transmitted by said second optical assembly are transmitted about said center optical axis of said second optical assembly, and wherein said second optical assembly includes an optical element that folds said center optical axis of said second optical assembly by an angle of more than 10 degrees, said second optical assembly having a longer best focus distance than said first optical assembly, said imaging lens of said second optical assembly having a longer focal length than said imaging lens of said first optical assembly;

an aiming pattern generator including a laser diode assembly, said aiming pattern generator projecting an aiming pattern;

a memory capable of storing a frame of image data, said frame of image data having image data representing light incident on said image sensor array; and

a CPU capable of addressing said memory, wherein said CPU is adapted to attempt to decode a decodable indicia represented in said frame of image data.

21. The indicia reading terminal of claim 20, wherein said aiming pattern generator is adapted to project said aiming pattern substantially at a horizontally extending centerline of said second field of view through a range of terminal to target distances.

22. An indicia reading terminal comprising:

a two dimensional image sensor array extending along an image plane, said two dimensional image sensor array comprising a plurality of pixels;

a hand held housing encapsulating said two dimensional image sensor array;

a first optical assembly having a center optical axis and an imaging lens, said first optical assembly for focusing imaging light rays onto a first set of pixels of said two dimensional image sensor array, wherein said imaging light rays transmitted by said first optical assembly are transmitted about said center optical axis of said first optical assembly;

a second optical assembly having a center optical axis and an imaging lens, said second optical assembly for focusing imaging light rays onto a second set of pixels of said two dimensional image sensor array, wherein said imaging light rays transmitted by said second optical assembly are transmitted about said center optical axis of said second optical assembly, and wherein said second optical assembly includes a precision manufactured double folding prism for folding said center optical axis of said second optical assembly at two locations, said double folding prism being precision manufactured by one of an injection molding process or an optical grinding process;

a memory capable of storing a frame of image data, said frame of image data representing light incident on said image sensor array; and

a CPU capable of addressing said memory, wherein said CPU is adapted to attempt to decode a decodable indicia represented in said frame of image data.

23. The indicia reading terminal of claim 22, wherein said first optical assembly is adapted so that said center optical axis of said first optical assembly is essentially unfolded.

24. The indicia reading terminal of claim 22, wherein said second optical assembly includes a longer best focus distance and a longer focal length than said first optical assembly, and wherein said indicia reading terminal is adapted so that a field of view defined by said second optical assembly and said image sensor array is defined, throughout a range of terminal to target distances from about 130 mm to about 420 mm, at a location within a field of view defined by said second optical assembly and said image sensor array throughout a range of terminal to target distances from about 130 mm to about 420 mm.