Back to results
US 9,792,943 B2Granted
Metal transmissive incremental encoding disk with index generation
AssigneeUS Digital LLC
InventorKurt Liebezeit
Life of this patent
Estimating the term…
Abstract
An optical encoder disk comprising an opaque disk, an outer track adjacent a peripheral edge of the disk, an inner index track defined by a first pattern of radial light-blocking elements subtending an arc within an annular band interposed between the outbound track and an axis of the disk, and an opaque support pattern of non-radial elements located within the annular band outside of the arc in which the index track is located formed of substantially non-radial elements. The inner index track further includes pattern apertures formed through the disk between the light-blocking elements so that light emitted on one face of the disk passes through the pattern apertures and falls upon photodetectors located adjacent an opposite face of the disk.
Claims18
An optical encoder mask, comprising:
- an opaque body;
- an outer track adjacent a peripheral edge of the mask;
- an inner index track defined by a first pattern of light blocking elements located within a width and at a first position of the index track and pattern apertures formed through the body between the light blocking elements so that light emitted on one face of the mask passes through the pattern apertures and falls upon photodetectors located adjacent an opposite face of the mask;
- and
- an opaque support pattern of elements located within the inner track outside of the index track, said support pattern defined by light blocking elements and apertures so that, within any position of the support pattern equal in width to the index track to the arc of the index track, at least a portion of the light emitted onto one face of the mask passes through the apertures of the support pattern and falls upon the photodetectors located adjacent the opposite face of the mask,
- wherein the opaque body is a disk, and wherein an inner index track subtends an arc within an annular band interposed between the outer track and an axis of the disk, the inner index track defined by a first pattern of radial light-blocking elements located at a first angular position of the index track and pattern apertures formed through the disk between the light-blocking elements so that light emitted on one face of the disk passes through the pattern apertures and falls upon photodetectors located adjacent an opposite face of the disk;
- and
- an opaque support pattern of non-radial elements located within the annular band outside of the arc in which the index track is located, said support pattern defined by light blocking elements and apertures so that, within any portion of the support pattern equal in width to the arc of the index track, at least a portion of the light emitted onto one face of the disk passes through the apertures of the support pattern and falls upon the photodetectors located adjacent the opposite face of the disk.
5 more elements
An optical encoder mask, comprising:
- an opaque body;
- an outer track adjacent a peripheral edge of the mask;
- an inner index track defined by a first pattern of light blocking elements located within a width and at a first position of the index track and pattern apertures formed through the body between the light blocking elements so that light emitted on one face of the mask passes through the pattern apertures and falls upon photodetectors located adjacent an opposite face of the mask;
- and
- an opaque support pattern of elements located within the inner track outside of the index track, said support pattern defined by light blocking elements and apertures so that, within any position of the support pattern equal in width to the index track to the arc of the index track, at least a portion of the light emitted onto one face of the mask passes through the apertures of the support pattern and falls upon the photodetectors located adjacent the opposite face of the mask,
- wherein the opaque body is a strip having a long axis defined along the length of the strip and short axis perpendicular to the long axis and including an inner index track subtending a width within the inner track and having a linear array of opaque portions and apertures formed between said portions and formed parallel to the short axis of the opaque body;
- and
- an opaque support pattern of elements located within the inner track outside of the width in which the index track is located, said support pattern defined by light blocking elements and apertures not formed parallel to the short axis of the opaque body so that, within any portion of the support pattern equal in width to the width of the index track, at least a portion of the light emitted onto one face of the strip passes through the apertures of the support pattern and falls upon the photodetectors located adjacent the opposite face of the strip.
5 more elements
An optical encoder, comprising:
- encoder disk having an outer track and inner index track, the inner track defined within an annular band of the disk and having an index pattern subtending an arc of the annular band with patterned opaque index portions and apertures formed between said portions, and a support pattern within the annular band outside of the index pattern;
- a light emitter located adjacent one face of the encoder disk and configured to project light onto the encoder disk and through the apertures;
- and
- photodetectors located adjacent an opposite face of the encoder disk from the light emitter, said photodetectors arranged in a photodetector pattern with an arrangement of a first type of photodetector matched with the patterned opaque index portions and an arrangement of a second type of photodetector matched with the apertures formed between said portions,
- wherein the support pattern on the encoder disk includes light blocking elements and apertures configured whereby, within any portion of the support pattern equal in width to the arc of the index pattern, at least a portion of the light emitted onto one face of the disk passes through the apertures of the support pattern and falls upon the photodetectors located adjacent the opposite face of the disk so that, when the support pattern is interposed between the light emitter and the photodetectors, more light falls on the photodetectors of the first type than of the second type.
2 more elements
Dependencies are inferred from the claim text.