Opto-electronic encoder with three-dimensional scales

• US 7,170,047 B2
• Filed: 07/19/2004
• Issued: 01/30/2007
• Est. Priority Date: 07/19/2004
• Status: Expired due to Fees

• Current Assignee: Anadish Kumar Pal
• Original Assignee: Anadish Kumar Pal
• Inventors: Pal, Anadish Kumar
• Primary Examiner(s): Luu; Thanh X.
• Assistant Examiner(s): Ko; Tony
• Application Number:
  US10/894,078
• Publication Number:
  US 20060011821A1
• Time in Patent Office: 925 Days
• Field of Search: 25023113-23118, 250/237.G, 250/231.1, 356/499
• US Class Current: 250/231.13
• CPC Class Codes: G01D 2205/95 Three-dimensional encoders, i.e. having codes extending in three directions
• CPC Class Codes: G01D 5/34 the beams of light being detected by photocells
• CPC Class Codes: G01D 5/347 using displacement encoding scales

Abstract

A single-, two- or three-axis opto-electronic encoder, or error-inputting device, with an optical scale which is overall cylindrical, spherical or volumetric, as opposed to extant planar, circular optical scales; mostly parallel rays of light enter from the cylindrical or spherical surface of the scale, travel, with or without being modulated in intensity due to rotation/rotations of, or distortion/distortions in, the scale, along elliptical and/or circular sectional planes of the scale and exit to fall upon an obstructing opto-electronic sensor or a plurality of such sensors. A photo-transmissive spherical float on a photo-opaque liquid sealed inside a spherical optical scale, moving vertically under the influence of an external force, upwardly displacing the photo-opaque liquid to block the light that enters the spherical optical scale from reaching any of the opto-electronic sensors, produces a distinct electronic condition for auxiliary use in addition to or conjunction with encoder or error-inputting device output or outputs.

Claims

1. An apparatus for directly producing encoded analogue and/or digital signals from a motion under the influence of a force or torque exerted varyingly by linked and/or external elements, for data processing and/or data logging, comprising:

orbicular confines to a spherical body and said spherical body rotatable relative to said orbicular confines under the influence of said force or torque;

said orbicular confines and said spherical body separately attachable to said linked and/or external elements, or separately integrable with said linked elements;

means arranged externally to said spherical body, connected to said orbicular confines, for emission of light directed to said spherical body along the circular sectional planes of said spherical body;

said spherical body having selective means for entry into, travel along and exit from said circular sectional planes of said spherical body of said light directed to said spherical body along said circular sectional planes;

means connected to said orbicular confines and positioned externally to said spherical body for opto-electronic detection of variations in said light after full crossing by said light of said selective means for entry into, travel along and exit from said circular sectional planes of said spherical body.

2. An encoding apparatus in accordance with claim 1, wherein said spherical body is outwardly a spherical body and inwardly a spherical cavity, with proximate geometrical centers, and is impervious to non-corrosive liquids and gases present outside said spherical body within temperatures of 0 degree to 70 degrees centigrade.

3. A spherical body in accordance with claim 2, wherein said spherical cavity is filled in volume with a gas or gases and a liquid solution and/or suspension non-toxic to life.

4. A spherical body in accordance with claim 3, wherein said spherical cavity in containment of, exclusive of said liquid, a small, spherical body of density less than that of said liquid in which is dissolved and/or suspended elements to render said liquid opaque to the wavelengths or bandwidth of said light effective for said opto-electronic detection of variations in said light, whereas said small, spherical body has high transmittance for said wavelengths or bandwidth of said light.

5. A spherical body in accordance with claim 4, wherein the absence of a vertically directed force on said spherical body has the upper horizontal level of said liquid filled in said volume of said spherical cavity to remain horizontally below said means for opto-electronic detection of variations in said light.

6. A spherical body in accordance with claim 4, wherein, due to the presence of said force, said small, spherical body in said containment of said spherical cavity displaces said liquid upwards to stop said light from said travel along said circular sectional planes of said spherical body and to reach said means for opto-electronic detection of variations in said light.

7. An encoding apparatus in accordance with claim 1, wherein said spherical body is a hollow, spherical ball with regular polygonal physical openings in the spherical surface of said spherical body distributed superficially in a uniform or coded pattern to act as said selective means for entry and exit of said light into and from said circular sectional planes of said hollow, spherical ball.

8. A spherical body in accordance with claim 1, wherein the center of gravity of said spherical body is markedly away from the geometrical center of said spherical body.

9. An encoding apparatus in accordance with claim 1, wherein said spherical body is wholly or selectively made of material having a high transmittance for wavelengths or bandwidth of said light to which the sensitivity of said means for opto-electronic detection of variations in said light is maximum.

10. An encoding apparatus in accordance with claim 1, wherein said means for emission of light include a light-emitting diode (LED) or an organic light-emitting device (OLED).

11. An encoding apparatus in accordance with claim 1, wherein said means for opto-electronic detection of variations in said light include a photodiode.

12. An encoding apparatus in accordance with claim 1, wherein said means for opto-electronic detection of variations in said light include a common-anode double photodiode.

13. An encoding apparatus in accordance with claim 1, wherein said means for opto-electronic detection of variations in said light include a phototransistor.

14. An encoding apparatus in accordance with claim 1, wherein said means for opto-electronic detection of variations in said light include two photodiodes connected to an integrated circuit (IC) containing other electronic components besides said photodiodes.

15. An encoding apparatus in accordance with claim 1, wherein said means for opto-electronic detection of variations in said light include a light-dependant resistor (LDR).

16. An encoding apparatus in accordance with claim 1, wherein said means for detection of variations in said light include a charge-coupled device (CCD).

17. An encoding apparatus in accordance with claim 1, wherein said selective means for entry and exit of said light into and from said circular sectional planes of said spherical body are internally proximate to the outer periphery of said spherical body.

18. An encoding apparatus in accordance with claim 1, wherein said selective means for entry and exit of said light into and from said circular sectional planes of said spherical body form the outer boundary to said spherical body.

19. An encoding apparatus in accordance with claim 1, wherein said selective means for travel along said circular sectional planes of said spherical body of said light are distributed homogeneously on said circular sectional planes of said spherical body.

20. An encoding apparatus in accordance with claim 1, wherein said selective means for travel along said circular sectional planes of said spherical body of said light are distributed in a regular or coded pattern on some or all of said circular sectional planes of said spherical body.