PHOTOELECTRIC REGISTRATION OF BALL ROTATION AS TEACHING AID FOR BALL GAMES

• US 3,630,601 A
• Filed: 02/24/1969
• Issued: 12/28/1971
• Est. Priority Date: 02/24/1969
• Status: Expired due to Term

• Current Assignee: Lehovec Kurt
• Original Assignee: Lehovec Kurt
• Inventors: LEHOVEC KURT
• Application Number:
  US04/801,396
• Time in Patent Office: 1,037 Days
• US Class Current: 356/256
• CPC Class Codes: A63B 2220/35 Spin
• CPC Class Codes: A63B 43/008 with means for improving visibility, e.g. special markings or colours illuminating or reflecting means A63B43/06
• CPC Class Codes: A63B 69/3658 Means associated with the ball for indicating or measuring, e.g. speed, direction
• CPC Class Codes: G09B 23/10 of solid bodies
• CPC Class Codes: Y10S 273/24 Luminescent, phosphorescent

Abstract

The ball is provided with a surface pattern of regions of different optical properties. Light reflected from the moving ball is modulated by the rotation of these regions, transformed into a time variable electrical signal in a photocell, and recorded or displayed.

Claims

1. An apparatus for registration of the rotational component of an unrestricted rotational motion of a substantially spherical body around an axis through the center oF said body, said axis of direction fixed in space, said apparatus comprising i. a pattern of optically distinct regions on the surface of said body, said pattern consisting of identically shaped spots equally spaced across said surface, ii. means to illuminate said body, iii. means to project an image of said body on a photocell, using light reflected from said body, iv. said photocell exposed only to a portion of said image of said body, said portion being strip-shaped, and oriented parallel to said axis of direction fixed in space, and v. electrical means to count or otherwise record the responses of said photocell to the images of said regions as they move through said strip-shaped portion due to said rotational component of motion of said spherical body around said axis.

2. The apparatus of claim 1 including means to keep said image of said spherical body centered with respect to said strip-shaped exposed portion.

3. The apparatus of claim 1 whereby said strip-shaped portion is narrower than the spacing between said spots.

4. The apparatus of claim 1 whereby said optically distinct regions differ in color from the background surface of said sphere.

5. The apparatus of claim 1 whereby said optically distinct regions differ in reflectivity from the background surface of said sphere.

6. The apparatus of claim 1 including a second photocell exposed to the image of a second strip-shaped portion of said spherical body, said second strip-shaped portion orthogonal to said strip-shaped portion of claim 21, electrical means to count or otherwise record the responses of said second photocell to the images of said regions as they move through said second strip-shaped portion, whereby the most general rotation of said body is resolved and fully characterized by its rotational components around said fixed axis of claim 21, and around a second axis of direction fixed in space, said second axis perpendicular to said axis of claim 21 and oriented parallel to said second strip-shaped portion.

7. The apparatus of claim 6 including means to center said second striplike portion with respect to said spherical body.

8. The apparatus of claim 1 whereby said spherical body is a bowling ball and said axis is chosen substantially perpendicular to the floor of the bowling alley.