Apparatus and method for monitoring hand washing

• US 6,038,331 A
• Filed: 02/17/1998
• Issued: 03/14/2000
• Est. Priority Date: 02/18/1997
• Status: Expired due to Term

• Current Assignee: Raymond C. Johnson
• Original Assignee: Raymond C. Johnson
• Inventors: Johnson, Raymond C.
• Primary Examiner(s): Johns, Andrew W.
• Application Number:
  US09/024,494
• Time in Patent Office: 756 Days
• Field of Search: 382/100, 382/115, 382/173, 382/180, 348/143, 4/619, 4/638, 4/661, 134/18, 134/56 R, 134/57 R, 134/58 R, 134/113, 604/289, 604/290
• US Class Current: 382/100
• CPC Class Codes: A47K 2210/00 Combinations of water taps, soap dispensers and hand dryers
• CPC Class Codes: G06T 2207/30196 Human being; Person
• CPC Class Codes: G06T 7/001 using an image reference approach
• CPC Class Codes: G06V 40/107 Static hand or arm
• CPC Class Codes: G08B 21/00 Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
• CPC Class Codes: G08B 21/245 Reminder of hygiene compliance policies, e.g. of washing hands

Abstract

An apparatus and method for monitoring hand washing wherein a subject'"'"'s hands are checked after he or she has applied soap or detergent and spread it over the front and back of his or her hands. An optical image of the subject'"'"'s hands is digitized and compared, pixel by pixel, with a reference feature that distinguishes the soap and a report is generated indicating whether the subject'"'"'s hands are covered with enough soap or detergent to receive a satisfactory report.

Claims

1. An apparatus for monitoring hand washing comprising

an input device in front of which a subject places his or her hands after he or she has applied and spread a layer of soap or detergent over the front and back of his or her hands, said input device converting light reflected from the soap and subject'"'"'s hands into an optical image,

a device for digitizing the optical image into a digitized image with a plurality of pixels,

a computer having an input for the digitized image and an output for a report,

a reference feature that distinguishes the soap from the subject'"'"'s hands, said reference feature in the computer,

an algorithm executed in the computer that compares the digitized image, pixel by pixel, with the reference feature and accumulates the number of pixels that match the reference feature, indicating the area to which soap is applied, and the number of pixels that do not match the reference feature, indicating the area of the hands to which soap has not been applied, calculates whether the number of pixels matching the reference feature out of the total number of pixels matching the reference feature plus the number pixels not matching the reference feature is greater than a predetermined level of coverage, and creates a report sent through the output.

2. An apparatus for monitoring hand washing comprising

a background in front of which a subject places his or her hands after he or she has applied and spread a layer of soap or detergent over the front and back of his or her hands,

an input device for converting light reflected from the background, soap and subject'"'"'s hands into an optical image,

a device for digitizing the image into a plurality of pixels,

a computer having an input for the digitized image and an output for a report,

a first reference feature that distinguishes the background from the soap and the subject'"'"'s hands and a second reference feature that distinguishes the soap from the background and the subject'"'"'s hands, said first and second reference features stored in the computer,

an algorithm executed in the computer that compares the digitized image, pixel by pixel, with the first and second reference features and accumulates the number of pixels that match the first reference feature, indicating the area to which soap is applied, or that matches neither reference feature, indicating the area of the hands to which soap has not been applied, calculates whether the number of pixels matching the second reference feature out of the total number of pixels matching the second reference feature plus the number pixels matching neither reference feature is greater than a predetermined level of coverage, and creates a report sent through the output.

3. The apparatus of claim 2 further comprising a video monitor in view of the subject for displaying the report.

4. The apparatus of claim 3 wherein the algorithm creates a second digitized image from said first digitized image, said second digitized image containing only those pixels that match the second reference feature, indicating the area to which soap is applied, or neither reference feature, indicating the area of the hands to which soap has not been applied, said second image in a form that the areas are visually distinguishable on a monitor, said second digitized image displayed on the video monitor.

5. The apparatus of claim 4 wherein the first digitized image is displayed on the video monitor for visual comparison with the second digitized image.

6. The apparatus of claim 2 further comprising a light source for illuminating a subject'"'"'s hands against the background.

7. A method for monitoring hand washing comprising

having a subject place his or her hands in front of a background after he or she has applied and spread a layer of soap or detergent over the front and back of his or her hands,

converting light reflected from the background, soap and subject'"'"'s hands into an optical image,

digitizing the image into a digitizing image with a plurality of pixels,

identifying a first reference feature that distinguishes the background from the soap and the subject'"'"'s hands and a second reference feature that distinguishes the soap from the background and the subject'"'"'s hands, said first and second reference features in a computer, and,

executing an algorithm in the computer that compares the digitized image, pixel by pixel, with the first and second reference features and accumulates the number of pixels that match the first reference feature, indicating the area to which soap is applied, or that matches neither reference feature, indicating the area of the hands to which soap has not been applied, calculates whether the number of pixels matching the second reference feature out of the total number of pixels matching the second reference feature plus the number pixels matching neither reference feature is greater than a predetermined level of coverage, and creates a report.

8. The method of claim 7 further comprising displaying the report on a video monitor in view of the subject.

9. The method of claim 8 wherein the algorithm creates a second digitized image from said first digitized image, said second digitized image containing only those pixels that match the second reference feature, indicating the area to which soap is applied, or neither reference feature, indicating the area of the hands to which soap has not been applied, said second image in a form that the areas are visually distinguishable on a monitor, said second digitized image displayed on the video monitor.

10. The method of claim 9 wherein the first digitized image is displayed on the video monitor for visual comparison with the second digitized image.