Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
168 words
An optical switch comprising: a first polarization converter; and a second polarization converter provided in series with the first polarization converter; operable said first and said second converter being to.select as emitted light one of two perpendicular polarized light components of incident light having a desired wavelength (λ 0 ) in polarized state; said first polarization converter converting said incident light having wavelength λ 0 into a polarized light component corresponding to one of two points positioned at opposite sides to each other on a Poincare sphere obtained by rotating said incident light +90° or -90° around an axis perpendicular to an axis passing through a point corresponding to said incident light on the Poincare sphere and the center of the Poincare sphere; said second polarization converter converting said polarized light obtained by said first polarization converter into polarized light corresponding to a point obtained by rotating said two polarized light components +90° or -90° around an axis passing through the above-mentioned two points on the Poincaré sphere.
Claim 2
Dependent Claim
168 words
An optical switch comprising: a first polarization converter; and a second polarization converter provided in series with the first polarization converter; operable said first and said second converter being to.select as emitted light one of two perpendicular polarized light components of incident light having a desired wavelength (λ 0 ) in polarized state; said first polarization converter converting said incident light having wavelength λ 0 into a polarized light component corresponding to one of two points positioned at opposite sides to each other on a Poincare sphere obtained by rotating said incident light +90° or -90° around an axis perpendicular to an axis passing through a point corresponding to said incident light on the Poincare sphere and the center of the Poincare sphere; said second polarization converter converting said polarized light obtained by said first polarization converter into polarized light corresponding to a point obtained by rotating said two polarized light components +90° or -90° around an axis passing through the above-mentioned two points on the Poincaré sphere.
Claim 3
Dependent Claim
33 words
An optical switch according to claim 1, wherein, in said first and second polarization converters, mutual conversion between the rotational angle of +90° and -90° on the Poincare sphere is simultaneously carried out.
Claim 4
Dependent Claim
27 words
An optical switch according to claim 1 or 2, wherein said first polarization converter is a Faraday rotator and said second polarization converter is an electro-optic element.
Claim 5
Dependent Claim
27 words
An optical switch according to claim 1 or 2, wherein said first polarization converter is an electro-optic element and said second polarization converter is a Faraday rotator.
Claim 6
Dependent Claim
37 words
An optical switch according to claim 1 or 2, wherein both said first and second polarization converters are Faraday rotators or electro-optic elements; a λ/4 phase difference device being provided between said first and second polarization converters.
Claim 7
Dependent Claim
21 words
An optical switch according to claim 3 or 4,wherein said Faraday rotator is a 45° Faraday rotator made of Yttrium-iron-garnet (YIG).
Claim 8
Dependent Claim
23 words
An optical switch according to claim 5, wherein both said first and second polarization converters are 45° Faraday rotators made of Yttrium-iron-garnet (YIG).
Claim 9
Dependent Claim
25 words
An optical switch according to claim 3 or 4, wherein said electro-optic element is lithium tantalate (LiTa0 3 ) or lithium niobate (LiNbO 3 ).
Claim 10
Dependent Claim
31 words
An optical switch according to claim 5, wherein both said first and second polarization converters are electro-optic devices made of lithium tantalate (LiTaO 3 ) or lithium niobate (LiNbO 3 ).