Apparatus for determining reflective color index of fibrous samples

Claim 2

In a colorimeter including a light source and optical means for directing light from the source into a path toward a color sample support, an apparatus for uniformly illuminating a randomly oriented fiber sample in said sample support comprising: a plurality of elongated optical light guides for directing light toward said support, said guides having opposite ends, one end of each guide being positioned below said support, said one ends being equispaced circumferentially around and equiangularly oriented upwardly toward the center of said support, at an angle of about 45* the other end of each guide being positioned in said path to receive light therefrom.

Claim 3

The apparatus as defined in claim 1 said optic light guides comprising polymethyl methocrylate fibers.

Claim 4

In a colorimeter including a light source and in optical alignment therewith a light filter, a convergent lens and a semitransparent mirror directing the light from said convergent lens into first and second paths toward a reference color support and a removable color sample support respectively, an apparatus for uniformly illuminating a randomly oriented fiber sample in said sample support with light from said second path said apparatus comprising: a. a ring positioned below said sample support and axially aligned therewith, said ring having cylindrical outer and inner surfaces, there being a plurality of passages connecting said outer and inner surfaces, said passages being equispaced circumferentially around said ring and angularly oriented upwardly toward said sample support at an angle of about 45*; and b. a plurality of optical light guides, for directing light toward said support, one end of each guide being fastened in a separate passage, the other end of each guide being positioned in said second path to receive light therefrom.

Claim 5

In a colorimeter including a light source and in optical alignment therewith a light filter, a convergent lens and a semitransparent mirror directing the light from said convergent lens into first and second paths toward a reference color support and a removable color sample support respectively, an apparatus for uniformly illuminating a randomly oriented fiber sample in said sample support with light from said second path said apparatus comprising: a. a ring positioned below said sample support and axially aligned therewith, said ring having cylindrical outer and inner surfaces, there being a plurality of passages connecting said outer and inner surfaces, said passages being equispaced circumferentially around said ring and angularly oriented upwardly toward said sample support at an angle of about 45*; and b. a plurality of optical light guides, for directing light toward said support, one end of each guide being fastened in a separate passage, the other end of each guide being positioned in said second path to receive light therefrom.

Claim 6

The apparatus as defined in claim 3, said optic light guides comprising polymethyl methacrylate fibers.

Claim 7

The apparatus as defined in claim 3, said inner surface having successive tapered and cylindrical lengths, said passages connecting said outer surface and said tapered length.

Claim 8

The apparatus as defined in claim 5, said one end of each guide being fastened in separate passages flush with said tapered length.

Claim 9

The apparatus as defined in claim 3 including the following additional elements; a pair of photodetectors, one viewing the sample and the other the reference, connected to circuit means for sensing electrical unbalance between the photocells; an auxiliary light guide having one end extended above said ring and directed toward said sample support; and light-actuated circuit means connected to said sensing circuit means, the other end of said auxiliary light guide being coupled to said light-actuated circuit means whereby removal of said sample support will allow outside light conducted by said auxiliary light guide to inactivate said sensing circuit means.