1. A frequency converting circuit comprising:
an impedance network having a first pair of terminals and operable to provide a first signal in a frequency band centered at a first frequency f1;
an output network having a second pair of terminals and a third pairs of terminals and configured to pass, between said second and third pairs of terminals, a second signal in a frequency band centered at a second frequency f2, where f2*f1, the third pair of terminals constituting output terminals connectable to an output component;
a pump circuit having a fourth pair of terminals and operative to provide, at said fourth pair of terminals, a third signal at a pump frequency fp, where fp\u2260f1 and f2; and
a frequency converter having a first port connected to said first terminals, a second port connected to said second pair of terminals and a third port connected to said fourth pair of terminals, said frequency converter being operative to cause the difference between f1 and f2 to be equal to fp.
2. The frequency converter of claim 1, wherein said impedance network comprises a bandpass or bandstop filter.
3. The frequency converter of claim 2, wherein said impedance network further comprises a negative resistance network connected to said filter and constituting a termination of said circuit.
4. The circuit of claim 1, wherein said output network comprises a bandpass filter.
5. The circuit of claim 1, wherein said pump circuit is operative to vary the pump frequency over a frequency band.
6. The circuit of claim 1, wherein said pump circuit is a tunable oscillator
7. The circuit of claim 1, wherein said frequency converter is an up-converter.
8. The circuit of claim 1, wherein said frequency converter is a down-converter.
9. The circuit of claim 1, in combination with the output component connected to said third pair of terminals of said output network.
10. The combination of claim 9, wherein said output component is a three-port circulator.
11. The combination of claim 10, wherein said circulator comprises an input port, an output port and an intermediate port, and said intermediate port is connected to said third pair of terminals of said output network.
12. The circuit of claim 1, wherein said output network comprises, in series between said second pair of terminals and said third pair of terminals, a first bandpass filter, a frequency up-converter and a second bandpass filter, and said circuit further comprises a second pump circuit having an output connected to said frequency up-converter, wherein said second pump circuit produces a signal at a second pump frequency different from the first pump frequency.
13. The circuit of claim 12, wherein each of said pump circuit and second pump circuit is a respective tunable oscillator.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A spectacle lens comprising:
a front surface;
a back surface;
a peripheral edge; and
a vision correcting area having a refractive error correction, wherein at least a portion of the refractive error correction is based on a lens prescription determined by a wave front analysis of a wearer’s eye and wherein the vision correcting area corrects non-conventional refractive error to provide at least a part of the wearer’s vision correction and wherein the peripheral edge is capable of being modified to fit within an eyeglass frame.
2. The lens of claim 1 wherein the vision correcting area corrects for conventional refractive error.
3. The lens of claim 1 wherein the vision correcting area corrects for aberrations of the lens.
4. The lens of claim 1 wherein the lens comprises a material having a variable index of refraction.
5. The lens of claim 1 wherein the lens comprises a material having a modifiable index of refraction.
6. The lens of claim 1 wherein the back surface is concave.
7. The lens of claim 1 wherein the lens is capable of correcting non-conventional refractive error caused by one of aberrations, irregular astigmatism, and ocular layer irregularities.
8. The lens of claim 1 wherein the lens provides a prismatic power.
9. The lens of claim 1 wherein the lens has a chromic characteristic.
10. The lens of claim 1 wherein correction of unconventional refractive error is provided by localized changes in a refractive power of the lens.
11. The lens of claim 1 wherein the lens corrects the wearer’s vision to better than 2020.
12. The lens of claim 1 wherein the lens corrects the wearer’s vision to better than 2010.
13. A method for producing a spectacle lens for the correction of non-conventional refractive error comprising:
determining a lens prescription for unconventional refractive error based in part on a wave front analysis of an eye.
providing a lens to correct for refractive error having a front surface, a back surface, a vision correcting area, and a peripheral edge;
modifying the lens to provide correction of least a portion of the lens prescription for unconventional refractive error;
modifying the peripheral edge of the lens to fit within an eyeglass frame; and
inserting the lens into the eyeglass frame.
14. The method of claim 13 wherein the lens provided is manufactured from a semi-finished lens blank.
15. The method of claim 13 wherein the unconventional refractive error is corrected in part by a refractive index change.
16. A spectacle lens comprising:
a front surface;
a back surface;
a peripheral edge; and
a vision correcting area having a refractive error correction, wherein the vision correcting area uses adaptive optics to correct for non-conventional refractive error to provide a wearer better than 2020 vision and wherein the peripheral edge is capable of being modified to fit within an eyeglass frame.