1. A portable headrest adapted for detachably engaging a chair with a seat back having front and rear surfaces, comprising:
a. an inflatable structure forming, when inflated, a base portion to rest against said front surface of said seat back, said base portion having means for wrapping around said rear surface of said seat back thereby releasably and securely holding said base portion against said seat back, and
b. a head-support portion that is adapted for extending far enough outward from said seat back such that said head-support portion will resist lateral bending of a user’s neck and lateral rotation of said user’s head, said head-support portion comprising a head-support surface being opposite said base portion such that said user’s head may rest laterally against said head-support surface and dorsally against said front surface of said seat back.
2. A headrest according to claim 1 wherein:
said inflatable structure comprises a substantially tear-drop shape.
3. A headrest according to claim 1 wherein:
said means for wrapping comprises a strap loop surrounding a strap and a slide-back stopper attached thereto, having such a shape as to prevent movement of said strap loop along said strap beyond said slide-back stopper, arranged such that the weight of said user’s head will exert a force such that said strap loop will engage said slide-back stopper, whereby said headrest will not move further along said strap in the direction away from said user’s head
4. A portable headrest adapted for a chair having a seat back with front and rear surfaces, comprising:
a. a base portion to rest against said front surface of said seat back, said base portion having means for wrapping around said front and rear surfaces of said seat back thereby releasably and securely holding said base portion against said seat back, and
b. a head-support portion, having a surface opposite from said base portion, that
(1) is connected to said base portion, adapted for extending far enough outward from said seat back such that said head-support portion will resist lateral bending of a user’s neck and lateral rotation of said user’s head, and
(2) receives said user’s head on said surface opposite from said base portion such that the back of said user’s head rests not against said base portion, but, when used in combination with said seat back, rests substantially against the plane of said front surface of said seat back.
5. A headrest according to claim 4 wherein:
said head-support portion additionally comprises a convex cushioning portion, on said surface opposite from said base portion, containing a deformable and resilient filler material, whereby said convex cushioning portion accommodates a variety of angles and positions relative to said user’s face, head, and neck.
6. A headrest according to claim 4, in which:
said means for wrapping comprises two straps, each of said straps having two ends, said two ends of each of said straps being attachable together with a length-adjustable buckle.
7. A headrest according to claim 4 wherein:
said head-support portion is engaged with said base portion with a hinged joint, said hinged joint being releasably locked at a chosen angle defined by the plane of said seat back and the plane of said head-support portion whereby said user may collapse said headrest into a smaller size for convenience in portability, and whereby said user may chose various such angles for positioning said head-support portion against said user’s face, head, and neck.
8. A headrest according to claim 4 wherein:
said head-support portion is engaged with said base portion with a pivoting means such that said head-support portion may pivot to various angles perpendicular to the plane of said seat back whereby said user may chose various such angles for positioning said head-support portion against said user’s face, head, and neck.
9. A headrest according to claim 4 wherein:
said head-support portion is engaged with said base portion at a substantially right angle.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for aligning a tape cartridge accessor with cartridges in cells of a tape cartridge magazine, comprising:
applying IR illumination to an object expected to include a desired physical feature;
receiving specular reflections from the illuminated object to create an image of the object;
applying dynamic image thresholding to the image to select an optimum gray scale level of the image expected to include the desired physical feature; and
using bounding boxes to identify the location of the desired physical feature in the thresholded image.
2. The method of claim 1 wherein the desired physical feature comprises a corner of a cell in a tape cartridge magazine.
3. The method of claim 1 wherein the applying dynamic image thresholding enhances relevant portions of the image and suppresses irrelevant portions of the image.
4. The method of claim 1 wherein the tape cartridge cells are used as fiducials to allow tape cartridge registration without fiducial markings.
5. The method of claim 4 wherein the use of the tape cartridge cells as fiducials maximizes storage capability.
6. An article of manufacture comprising a program storage medium readable by a computer, the medium tangibly embodying one or more programs of instructions executable by the computer to perform a method for aligning a tape cartridge accessor with cartridges in cells of a tape cartridge magazine, the method comprising:
applying IR illumination to an object expected to include a desired physical feature;
receiving specular reflections from the illuminated object to create an image of the object;
applying dynamic image thresholding to the image to select an optimum gray scale level of the image expected to include the desired physical feature; and
using bounding boxes to identify the location of the desired physical feature in the thresholded image.
7. The article of manufacture of claim 6 wherein the desired physical feature comprises a corner of a cell in a tape cartridge magazine.
8. The article of manufacture of claim 6 wherein the applying dynamic image thresholding enhances relevant portions of the image and suppresses irrelevant portions of the image.
9. The article of manufacture of claim 6 wherein the tape cartridge cells are used as fiducials to allow tape cartridge registration without fiducial markings.
10. The article of manufacture of claim 9 wherein the use of the tape cartridge cells as fiducials maximizes storage capability.