Patent US5748369A successfully refreshed from Google Patents.
US5748369A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polarizing beam splitter and an illuminating device provided with the same
Assignee: Canon Inc
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Filing: 1995-09-28
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Granted: 1998-05-05
•
Expires: 2015-09-28
Abstract
Abstract This invention relates to a polarizing beam splitter and an illuminating device having the polarizing beam splitter. The polarizing beam splitter of this invention comprises a transparent flat plate and films of a dielectric material provided on the opposite surfaces of the plate.
Inventors
- 👤 Hideo Yokota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:34
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/28; G02B27/283; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/13362
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
166 words
A device for illuminating an object to be illuminated with light from a light source, said device comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 2
Independent Claim
166 words
A device for illuminating an object to be illuminated with light from a light source, said device comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 3
Dependent Claim
38 words
A device according to claim 1, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light so that interference of light is not generated in said films.
Claim 4
Dependent Claim
28 words
A device according to claim 1, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
Claim 5
Independent Claim
303 words
A device for illuminating an object to be illuminated with light from a light source, said device comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 6
Independent Claim
303 words
A device for illuminating an object to be illuminated with light from a light source, said device comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 7
Dependent Claim
38 words
A device according to claim 4, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light so that interference of light is not generated in said films.
Claim 8
Dependent Claim
28 words
A device according to claim 4, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
Claim 9
Independent Claim
176 words
An apparatus for forming an image by illuminating a light valve with light from a light source, said apparatus comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films between said light source and said light valve to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 10
Independent Claim
176 words
An apparatus for forming an image by illuminating a light valve with light from a light source, said apparatus comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films between said light source and said light valve to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 11
Dependent Claim
38 words
An apparatus according to claim 7, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light so that interference of light is not generated in said films.
Claim 12
Dependent Claim
28 words
An apparatus according to claim 7, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
Claim 13
Independent Claim
313 words
An apparatus for forming an image by illuminating a light valve with light from a light source, said apparatus comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member between said light source and said light valve, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 14
Independent Claim
313 words
An apparatus for forming an image by illuminating a light valve with light from a light source, said apparatus comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member between said light source and said light valve, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 15
Dependent Claim
38 words
An apparatus according to claim 10, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light so that interference of light is not generated in said films.
Claim 16
Dependent Claim
28 words
An apparatus according to claim 10, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
Claim 17
Dependent Claim
162 words
An optical apparatus for processing light from a light source, said optical apparatus comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 18
Dependent Claim
162 words
An optical apparatus for processing light from a light source, said optical apparatus comprising: a transparent flat plate; beam splitting films provided on opposite surfaces of said transparent flat plate, wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films to produce a transmitted light of said other one of said beam splitting films, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films be the same as said single polarization direction of light.
Claim 19
Dependent Claim
39 words
An optical apparatus according to claim 13, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light, so that interference of light is not generated in said films.
Claim 20
Dependent Claim
29 words
An optical apparatus according to claim 13, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
Claim 21
Dependent Claim
299 words
An optical apparatus for processing light from a light source, said optical apparatus comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 22
Dependent Claim
299 words
An optical apparatus for processing light from a light source, said optical apparatus comprising: a first member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate; wherein each of said beam splitting films has a transmittance characteristic such that transmittance of P-polarized light is different from transmittance of S-polarized light, wherein a transmitted light from one of said beam splitting films includes said P-polarized light and said S-polarized light, and a reflected light of said one of said beam splitting films contains substantially only a single polarization direction of light; wherein the other one of said beam splitting films resplits said transmitted light from said one of said beam splitting films, and a second member including a transparent flat plate and beam splitting films provided on opposite surfaces of said transparent flat plate of said second member, wherein each of said beam splitting films of said second member has a transmittance characteristic which is different with respect to P-polarized light and S-polarized light, wherein a transmitted light from one of said beam splitting films of said second member includes said P-polarized light and said S-polarized light, wherein the other one of said beam splitting films of said second member resplits said transmitted light from said one of said beams splitting films of said second member to produce a transmitted light of said other one of said beam splitting films of said second member; said transparent flat plate of said second member being provided parallel to said transparent flat plate of said first member, and a polarization changing plate for making the polarization direction of said transmitted light of said other one of said beam splitting films of said second member be the same as said single polarization direction of light.
Claim 23
Dependent Claim
39 words
An optical apparatus according to claim 16, wherein the distance between said beam splitting films on said opposite surfaces is sufficiently greater than the wavelength of incident light, so that interference of light is not generated in said films.
Claim 24
Dependent Claim
29 words
An optical apparatus according to claim 16, wherein said beam splitting films transmit therethrough most of the P-polarized light of light incident at an angle of incidence of 45°.
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