Non-reflective graphic surface
AssigneeTIR Systems Ltd.
InventorLorne A. Whitehead
Life of this patent
Estimating the term…
Abstract
A graphic surface display device comprises a graphic surface be displayed and a cover of substantially transparent material overlying and in optical contact with the graphic surface. The cover has a minutely textured outer surface such that the angle between a first vector normal to a randomly selected point on the cover's surface; and, a second vector which passes through the selected point and which is normal to a plane tangential to the graphic surface at the point of intersection of the second vector with the graphic surface; has substantially unity probability of exceeding 45.degree..
Claims27
A graphic surface display device, comprising:
- (a) a graphic surface to be displayed;
- and,
- (b) a cover of substantially transparent material overlying said graphic surface, said cover having a minutely textured outer surface wherein an angle .phi..sub.1 between:
- (i) a first vector normal to a randomly selected point on said outer surface;
- and,
- (ii) a second vector which passes through said selected point and which is normal to a plane tangential to said graphic surface at the point of intersection of said second vector with said graphic surface;
- has substantially unity probability of exceeding 45.degree..
A window comprising a substantially transparent material having minutely textured, first and second surfaces on opposed sides of a notional reference surface, wherein an angle .phi..sub.1 between:
- (i) a first vector normal to a randomly selected point of said first surface;
- and,
- (ii) a second vector which passes through said selected point and which is normal to a plane tangential to said reference surface at the point of intersection of said second vector with said reference surface;
- has substantially unity probability of exceeding 45.degree.;
- and wherein an angle .phi..sub.2 between:
- (iii) a third vector normal to a randomly selected point on said second surface;
- and,
- (iv) a fourth vector which passes through said selected second surface point and which is normal to a plane tangential to said reference surface at the point of intersection of said fourth vector with said reference surface;
- is greater than or equal to:
- 4.degree.+1/2 (.phi..sub.min -sin .sup.-1 ((1/n) sin .phi..sub.min))
- where "n" is the refractive index of said material, where .phi..sub.min is the greatest for which it is true for substantially all points on said first surface that .phi..sub.1 >.phi..sub.min.
Dependencies are inferred from the claim text.