Visible and infrared polarization ratio spectroreflectometer

Claim 2

An instrument for measuring the intensity of polarized light reflected from a surface, the combination comprising: (a) a sample surface; (b) a reference surface; (c) multiple light sources; (d) light selection and chopping means for selecting the light from one of said multiple light sources, chopping the light signal at a predetermined frequency, and focusing the light onto said sample surface; (e) continuously rotating light polarizing means positioned between said sample surface and said light selection and chopping means and wherein said continuously rotating light polarizing means continuously changes the plane of polarization of the light from 0° to 360°; (f) detection means for selectively sensing and analyzing light reflected from said sample surface and said reference surface; (g) sample spinner means connected to said light selection and chopping means and positioned between said light selection and chopping means and said detection means for supporting said sample surface and said reference surface; and (h) aligning means for automatically aligning said light selection and chopping means, said sample spinner means, and said detection means while the angle of incidence is changed continuously or otherwise, so that the light from said light selection and chopping means upon striking said sample surface will reflect from said sample surface and impinge on said detection means.

Claim 3

An instrument as in claim 1 wherein said detection means comprises: a monochromator; an infrared detector; a visible light detector; and a selecting mirror within said monochromator for selectively directing the light onto either said infrared detector or onto said visible light detector.

Claim 4

An instrument as in claim 1 wherein said light selection and chopping means comprises: (a) a rotatable selecting mirror for selecting the light from one of said multiple light sources; (b) a reflecting mirror that receives the light reflected from said source selecting mirror; (c) a chopper disposed between said source selecting mirror and said reflecting mirror for chopping the light signal at a predetermined frequency; and (d) a focusing mirror for receiving the light reflected from said reflecting mirror and focusing the light into said sample surface.

Claim 5

An instrument as in claim 1 wherein said multiple light sources comprise: a first light source; a second light source; said first light source being a visible light lamp; and said second light source being an infrared light lamp.

Claim 6

An instrument as in claim 1 wherein said continuously rotating light polarizing means comprises: (a) a rotatable polarizer holder positioned between said light selection and chopping means and said sample surface; (b) a polarizer motor drive for rotating said polarizer holder to change the plane of polarization of the light from 0° to 360°; and (c) a polarizing element releasably attached to said polarizer holder to provide polarized incident light directly on said sample surface; wherein said polarizing element is selected from a plurality of interchangeable polarizing elements including a visible light polarizer and an infrared light polarizer.

Claim 7

An instrument as in claim 1 wherein said aligning means comprises: (a) a rotating arm platform; (b) a rotating sample platform; said rotating arm platform rotating about the said axis as said rotating sample platform; the rotation of said arm platform being coupled with the rotation of said sample platform such that the angular rotation of said arm platform is twice that of said sample platform; said sample spinner means being positioned on said rotating sample platform; (c) a fixed arm platform; (d) a focusing mirror; said fixed arm platform supporting said focusing mirror which receives the light reflected from said sample surface and focuses the light onto said detection means; and (e) drive means for rotating said sample platform and said arm platform.

Claim 8

An instrument as in claim 6 wherein said drive means comprises: a motor for rotating said sample platform and said arm platform automatically; and a crank for selectively rotating said sample platform and said arm platform manually.

Claim 9

An instrument for measuring the intensity of polarized light reflected from a surface, the combination comprising: (a) a sample surface; (b) a reference surface; (c) source means for generating a light signal that impinges on said sample surface and said reference surface; (d) detection means for selectively sensing and analyzing light reflected from said sample surface and said reference surface; (e) a rotating arm platform; (f) a rotating sample platform; said rotating arm platform rotating about the same axis as said rotating sample platform; the rotation of said arm platform being coupled with the rotation of said sample platform such that the angular rotation of said arm platform is twice that of said sample platform; (g) a fixed arm platform; (h) a focusing mirror; said fixed arm platform supporting said focusing mirror which receives the light reflected from said sample surface and focuses the light onto said detection means; (i) drive means for rotating said sample platform and said arm platform; (j) a sample holder positioned on said rotating sample platform; (k) a reference holder for holding said reference surface positioned on said rotating sample platform; (l) a post rigidly attached to and perpendicular to said sample platform; (m) a rotatable sample spinner disc, said spinner disc being adapted to accept said reference holder and said sample holder, said spinner disc being releasably attachable to said post and rotatable thereon about an axis perpendicular to the axis of rotation of said sample platform so as to place said sample surface and said reference surface alternately in the path of the light directed by said source means; (n) a pair of mountings attached to said sample spinner disc to accept said sample holder and said reference holder, said sample holder and said reference holder being cylindrical with the bottom surfaces thereof provided with a diametric groove, the outside surfaces thereof being threaded and the top portion of said sample holder being recessed to receive said sample surface, said mountings being annular rings threaded on the inside surface thereof to receive and support, respectively, said sample holder and said reference holder, said sample holder and said reference holder being rotatable within said mountings so that said sample surface and said reference surface coincide with the axis of rotation of said sample platform, said mountings being adjustable by screws extending through springs positioned between said mounting and the front surface of said sample spinner disc, said screws being positioned near the perimeter of said mountings at equal intervals to enable compensatory adjustments for surface irregularities of said sample surface and said reference surface; and (o) a motor to rotate said sample spinner disc upon said post.

Claim 10

An instrument for measuring the intensity of polarized light reflected from a surface, the combination comprising: (a) a sample surface; (b) a reference surface; (c) source means for generating a light signal that impinges on said sample surface and said reference surface; (d) detection means for selectively sensing and analyzing light reflected from said sample surface and said reference surface; (e) a rotating arm platform; (f) a rotating sample platform; said rotating arm platform rotating about the same axis as said rotating sample platform; the rotation of said arm platform being coupled with the rotation of said sample platform such that the angular rotation of said arm platform is twice that of said sample platform; (g) a fixed arm platform; (h) a focusing mirror; said fixed arm platform supporting said focusing mirror which receives the light reflected from said sample surface and focuses the light onto said detection means; (i) drive means for rotating said sample platform and said arm platform; (j) a sample holder positioned on said rotating sample platform; (k) a reference holder for holding said reference surface positioned on said rotating sample platform; (l) a post rigidly attached to and perpendicular to said sample platform; (m) a rotatable sample spinner disc, said spinner disc being adapted to accept said reference holder and said sample holder, said spinner disc being releasably attachable to said post and rotatable thereon about an axis perpendicular to the axis of rotation of said sample platform so as to place said sample surface and said reference surface alternately in the path of the light directed by said source means; (n) a pair of mountings attached to said sample spinner disc to accept said sample holder and said reference holder, said sample holder and said reference holder being cylindrical with the bottom surfaces thereof provided with a diametric groove, the outside surfaces thereof being threaded and the top portion of said sample holder being recessed to receive said sample surface, said mountings being annular rings threaded on the inside surface thereof to receive and support, respectively, said sample holder and said reference holder, said sample holder and said reference holder being rotatable within said mountings so that said sample surface and said reference surface coincide with the axis of rotation of said sample platform, said mountings being adjustable by screws extending through springs positioned between said mounting and the front surface of said sample spinner disc, said screws being positioned near the perimeter of said mountings at equal intervals to enable compensatory adjustments for surface irregularities of said sample surface and said reference surface; and (o) a motor to rotate said sample spinner disc upon said post.

Claim 11

An instrument as in claim 8 wherein said sample holder is selected from a plurality of sample holders of varying sizes to accept samples of varying sizes.

Claim 12

An instrument as in claim 9 wherein said sample spinner disc is selected from a plurality of diverse size sample spinner discs each adapted to accept a sample holder of a particular size.