Portable viewer for invisible bar codes

• US 6,177,683 B1
• Filed: 11/25/1998
• Issued: 01/23/2001
• Est. Priority Date: 11/25/1998
• Status: Expired due to Fees

• Current Assignee: C2IT
• Original Assignee: C2IT LLC
• Inventors: DeRome, Gerard A., Kolesar, Jason R., Kapturowski, Edward J., Guberski, James M.
• Primary Examiner(s): Allen, Stephone B.
• Application Number:
  US09/200,312
• Time in Patent Office: 790 Days
• Field of Search: 250/566, 250/568, 250/239, 235/462.01, 235/462.46, 235/468, 235/470, 235/491
• US Class Current: 250/566
• CPC Class Codes: G06K 7/10722 Photodetector array or CCD scanning
• CPC Class Codes: G06K 7/12 using a selected wavelength, e.g. to sense red marks and ignore blue marks

Abstract

A portable viewer for viewing bar codes and other markings printed at least in part with invisible inks includes a light source for illuminating and exciting the ink of the bar code, a camera for detecting light emitted by the excited bar code and for outputting image data, a display for creating a visible image of the bar code from the image data output from the camera, and an optical system for projecting the visible image onto a viewing screen. The display may be a miniature, transmissive active matrix liquid crystal display with high resolution that produces a sharp, bright image. A backlight and lens project the image produced by the display to generate an enlarged virtual image that can be easily viewed by a user. The portable viewer is compact in size and can be accommodated in a small package and requires only a small amount of power.

Claims

1. A portable viewer for viewing markings that are at least partially invisible ink markings, the invisible ink emitting light at an emission frequency in response to light of an excitation frequency being impinged thereon, comprising:

a) a light source for generating light at the excitation frequency;

b) a camera sensitive to light at said emission frequency for detecting the image created by said emitted light in response to light from said light source impinging upon the invisible ink;

c) a display for displaying, in the visible spectrum, the image detected by said camera; and

d) a magnifying optical system disposed between said display and the user for magnifying the image on said display.

5. The portable viewer of claim 1 wherein said light source is a plurality of light emitting diodes.

6. The portable viewer of claim 5 wherein said light emitting diodes emit light across a spectrum of wavelengths with a peak wavelength of approximately 660 nm.

7. The portable viewer of claim 1 wherein said markings are entirely invisible ink markings.

8. The portable viewer of claim 1 wherein said display has dimensions no larger than 2{fraction (5/16)} inch by 1{fraction (9/16)} inch by 4⅝

inch.

9. The portable viewer of claim 1 wherein said magnifying optical system magnifies the image on the display for the user by at least five times.

10. The portable viewer of claim 1 further including a backlight for said display.

11. The portable viewer of claim 10 wherein said backlight and said display consume not more than approximately 20 mW combined.

12. The portable viewer of claim 1 further including a light switch for controlling said light source.

13. The portable viewer of claim 1 wherein said camera includes an input and further including an ambient light sensor disposed near said camera input.

14. The portable viewer of claim 1 further including a housing, said housing enclosing said light source, said camera, said display, and said magnifying optical system.

15. The portable viewer of claim 14 further including a cover disposed around said housing and moveable between a storage position and a deployed position, wherein said cover functions as a shroud for said camera in said deployed position.

16. The portable viewer of claim 15 wherein said shroud is moveable longitudinally with respect to said housing between said storage position and said deployed position.

2. The portable viewer of 1 further including a filter in the optical path leading to said camera, said filter selectively allowing light in a predetermined frequency band to pass through to said camera.

3. The portable viewer of claim 2 wherein the predetermined band pass frequency band of said filter is approximately 700 nm to approximately 1200 nm.

4. The portable viewer of claim 2 wherein said filter substantially blocks light at the excitation frequency.

17. A portable viewer for viewing invisible ink markings, the invisible ink emitting light at an emission frequency in response to light of an excitation frequency being impinged thereon, comprising:

a) a plurality of light emitting diodes for generating light at the excitation frequency;

b) a camera sensitive to light at said emission frequency for detecting the image created by said emitted light in response to light from said light source impinging upon the invisible ink;

c) a filter in the optical path leading to said camera, said filter selectively allowing light having a frequency in a predetermined frequency band to pass therethrough to said camera;

said frequency band including said emission frequency;

said filter substantially blocking light at the excitation frequency;

d) a transmissive LCD display for displaying, in the visible spectrum, the image detected by said camera;

e) a backlight for said display;

f) a magnifying optical system disposed between said display and the user of the viewer for magnifying the image on said display for the user by at least five times;

g) a housing enclosing said light source, said camera, said display, said backlight, and said magnifying optical system; and

h) wherein said backlight and said display consume not more than approximately 20 mW combined.

18. The portable viewer of claim 17 wherein said display has dimensions no larger than 2{fraction (5/16)} inch by 1{fraction (9/16)} inch by 4⅝

inch.

19. The portable viewer of claim 17 wherein said light emitting diodes emit light across a spectrum of wavelengths with a peak wavelength of approximately 660 nm and wherein the predetermined band pass frequency band of said filter is approximately 700 nm to approximately 1200 nm.

20. The portable viewer of claim 17 wherein said camera includes an input and further including an ambient light sensor disposed near said camera input;

said ambient light sensor generating an alarm when the ambient light at said emission frequency sensed at said ambient light sensor is above a predetermined level.

21. The portable viewer of claim 17 further including a cover disposed generally around said housing and moveable between a deployed position and a storage position;

said cover forming a shroud for said camera in said deployed position.

22. A portable viewer for viewing invisible ink markings, the invisible ink emitting light at an emission frequency in response to light of an excitation frequency being impinged thereon, comprising:

a) a housing;

b) a camera disposed in said housing for detecting the invisible markings and generating an image of the invisible markings;

c) a display operatively connected to said camera for displaying the image to a user;

d) a light shroud for shielding said camera from ambient light;

said shroud moveable between a deployed position and a storage position.

23. The portable viewer of 22 wherein said light shroud comprises a sheath surrounding said housing.

24. The portable viewer of claim 23 wherein said sheath includes a main body and a pair of flexible end flaps attached to opposing ends of said main body that fold up to substantially enclose said housing.