1. Apparatus for focusing a light, comprising:
a waveguide; and
a curved grating formed in the waveguide, the grating adapted to focus the light incident on the waveguide to a focused spot at a first end of the waveguide, wherein the first end is tangent to, or passes through the focused spot, wherein a thickness of the waveguide at the first end is greater than a thickness of the waveguide at the grating.
2. (canceled)
3. The apparatus of claim 1, wherein a ratio of thickness of the waveguide at the first end relative to a thickness of the waveguide at the grating is at least about 4:1.
4. The apparatus of claim 1, wherein a ratio of thickness of the waveguide at the first end relative to a thickness of the waveguide at the grating is between about 1:1 to about 5:1.
5. The apparatus of claim 1, wherein the first end of the waveguide has a greater refractive index greater than a portion of the waveguide containing the grating.
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. The apparatus of claim 1 further comprising:
an induction coil positioned proximate the first end of the waveguide.
11. (canceled)
12. (canceled)
13. The apparatus of claim 10 further comprising:
a light source adapted for selectively illuminating the grating with a light; and
a magnetic storage medium positioned proximate the first end.
14. The apparatus of claim 13, wherein the grating is adapted to focus the light incident on the grating to a focus spot proximate the first end, and wherein a diameter of the focus spot is expressed as:
d
spot
=
\u03bb
2.25
\u2062
n
sil
wherein;
nsil is the refractive index of a layer in which the light is propagating;
dspot is the diameter of the focused spot; and
\u03bb is the wavelength the light.
15. The apparatus of claim 13, wherein the grating is adapted to focus the light incident on the grating to a focus spot proximate the first end, and wherein a diameter of the focus spot is expressed as:
d
spot
=
\u03bb
\u2062
r
2
+
d
2
2.25
\u2062
n
sil
\u2062
r
wherein:
d is the distance between the center of the incident spot of light on the grating and the center of the focus spot;
dspot is the diameter of the focused spot;
nsil is the refractive index of a layer of the waveguide in which the light is propagating;
\u03bb is the wavelength the light; and
r is the radius of the incident spot
16. (canceled)
17. The apparatus of claim 13, wherein the first end of the waveguide has a greater refractive index than a portion of the waveguide containing the grating,
18. The apparatus of claim 13, wherein the magnetic storage medium is positioned within a near field of the focused spot.
19. The apparatus of claim 18, wherein the waveguide includes regions of a layer of material having different refractive indexes.
20. The apparatus of claim 13, wherein the grating is illuminated at a substantially normal incidence.
21. Apparatus for focusing a light, comprising:
a waveguide; and
a curved grating formed in the waveguide, the grating adapted to focus the light incident on the waveguide to a focused spot at a first end of the waveguide, wherein the first end is tangent to, or passes through the focused spot, wherein the first end of the waveguide has a greater refractive index greater than a portion of the waveguide containing the grating.
22. The apparatus of claim 21 further comprising:
an induction coil positioned proximate the first end of the waveguide.
23. The apparatus of claim 22, wherein the first end of the waveguide has a thickness greater than a portion of the waveguide having the grating formed therein.
24. The apparatus of claim 22 further comprising:
a light source adapted for selectively illuminating the grating with a light; and
a magnetic storage medium positioned proximate the first end.
25. The magnetic recording device of claim 22, wherein the magnetic storage medium is positioned within a near field of the focused spot.
26. Apparatus for focusing a light, comprising:
a waveguide;
a curved grating formed in the waveguide and adapted to focus the light incident on the waveguide;
a structure positioned on the waveguide to focus light received from the grating to a spot at a first end of the waveguide, wherein the first end is tangent to, or passes through the focused spot.
27. The apparatus of claim 26, wherein the structure extends from a plane of the waveguide
28. The apparatus of claim 26, wherein the structure has a greater refractive index than a portion of the waveguide containing the grating.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Device for optically capturing objects, comprising:
a support surface (1) on whose first side an object can be placed,
a light source (4) which is provided for emitting illuminating beams (2, 3) in the direction of the support surface (1) and which, in a first position, is arranged relative to the support surface (1), and
a capturing means (5) which is provided for capturing the object placed on the support surface (2)- and optionally for converting the image of the captured object into electrical signals\u2014and which, in a second position, is arranged relative to the support surface (1),
wherein the first side of the support surface (1), on which the object can be placed, faces the illuminating beams (2, 3) and the capturing means (5), characterized in that the first side of the support surface (1) has a flat region (16) and\u2014adjacent to this\u2014a section (6) which is provided with a curvature determined by the two positions and which is arranged in such a way that the illuminating beams (3) are reflected by the section (6) in the direction of the capturing means substantially only in a diffuse manner.
2. Device for optically capturing objects according to claim 1, characterized in that the section (6) has a curvature only in the direction of the capturing means (5).
3. Device for optically capturing objects according to claim 1, characterized in that the curvature corresponds\u2014in perpendicular cross-section\u2014to a segment of a conic section (20).
4. Device for optically capturing objects according to claim 1, characterized in that a back-lit, discrete slide capturing region (7) having a mechanical, point-discrete positioning aid (8) for the accurate positioning of at least one first slide (9) is coordinated with the support surface (1).
5. Device for optically capturing objects according to claim 4, characterized in that a back-lit preview region (10) is provided which is adjacent to the slide capturing region (7) and with which a mechanical, line-discrete positioning aid (11) for positioning at least one further slide (12) on a line is coordinated.
6. Device for optically capturing objects according to claim 4, characterized in that the capturing means (5) is rotatable relative to the support surface (1), and the capturing means (5) can be repetitively oriented with the discrete slide capturing region (7) by means of a locking element.