1. A Moir\xe9 interferometric-based shear-stress sensor, comprising:
a substrate support, said substrate including a first optical grating disposed in or on said substrate, said first grating having a plurality of features defining a first spatial period, and
a floating element having a second optical grating disposed in or on said floating element, said second grating having a plurality of features defining a second spatial period, said floating element suspended over said first grating and flexibly connected to said substrate with compliant springs, wherein said first and second gratings are in an optical path with one another, said sensor upon irradiation forming a Moir\xe9 fringe pattern which relates to a shear-stress induced translation of said floating element.
2. The sensor of claim 1, wherein said substrate support is substantially optically transparent.
3. The sensor of claim 1, wherein said sensor is a MEMS sensor.
4. The sensor of claim 3, wherein said floating element comprises silicon.
5. The sensor of claim 4, wherein said silicon is single crystal silicon.
6. The sensor of claim 1, wherein a ratio of fringe pitch (G) to a pitch of said second grating is at least 10.
7. A sensor system for measuring shear-stress, comprising:
A Moir\xe9 interferometric-based shear-stress sensor including a substrate support, said substrate including a first optical grating disposed in or on said substrate, said first grating having a plurality of features defining a first spatial period, and a floating element having a second optical grating disposed in or on said floating element, said second grating having a plurality of features defining a second spatial period, said floating element suspended over said first grating and flexibly connected to said substrate with compliant springs, wherein said first and second gratings are in an optical path with one another, said sensor upon irradiation forming a Moir\xe9 fringe pattern which relates to a shear-stress induced translation of said floating element;
a light source for irradiating said sensor with electromagnetic radiation, and
a detector for measuring fringe patterns resulting from reflections of said radiation from said first and second grating.
8. A method for measuring shear-stress, comprising the steps of:
providing a Moir\xe9 interferometric-based shear-stress sensor including a pair of gratings in an optical path and a floating element;
irradiating said sensor with electromagnetic radiation;
measuring a Moir\xe9 fringe pattern resulting from reflections of said radiation from said pair of gratings, and
using said Moir\xe9 fringe pattern for determination of displacement of said floating element to determine shear-stress.
9. The method of claim 8, wherein one of said pair of gratings comprises a grating disposed in or on said floating element.
10. The method of claim 8, wherein said sensor is a MEMS sensor, said MEMS sensor including a semiconducting or dielectric substrate.
11. The method of claim 10, wherein said substrate is substantially optically transparent to said electromagnetic radiation.
12. The method of claim 11, wherein said step of irradiating said sensor comprises applying incident radiation to said substrate.
13. The method of claim 10, wherein said substrate is single crystal silicon and said floating element is formed from said single crystal silicon.
14. The method of claim 10, wherein said substrate comprises silicon-on-insulator (SOI).
15. The method of claim 14, wherein said floating element formed in or on a Si-overlayer of said SOI substrate.
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. A zoom lens consisting, in order from an object side thereof, of:
a front side lens unit having a negative refracting power at a wide angle end; and
a rear side lens unit having a positive refracting power at the wide angle end, wherein
the front side lens unit comprises a first lens unit located closest to the object side and having a positive refracting power and a second lens unit located on an image side of the first lens unit and having a negative refracting power, the distance between the first lens unit and the second lens unit being larger at a telephoto end than at the wide angle end,
the rear side lens unit comprises a third lens unit located closer to the object side at the telephoto end than at the wide angle end and having a positive refracting power, the distance between the third lens unit and the second lens unit being smaller at the telephoto end than at the wide angle end, and
the third lens unit satisfies the following condition:
0.01<f3ft<0.16\u2003\u2003(1)
where f3 is a focal length of the third lens unit, and ft is a focal length of the entire zoom lens system at the telephoto end,
wherein the second lens unit satisfies the following condition:
0.01<|f2|ft<0.10\u2003\u2003(3)
where f2 is a focal length of the second lens unit, and ft is the focal length of the entire zoom lens system at the telephoto end.
2. A zoom lens consisting, in order from an object side thereof, of:
a front side lens unit having a negative refracting power at a wide angle end; and
a rear side lens unit having a positive refracting power at the wide angle end, wherein
the front side lens unit comprises a first lens unit located closest to the object side and having a positive refracting power and a second lens unit located on an image side of the first lens unit and having a negative refracting power, the distance between the first lens unit and the second lens unit being larger at a telephoto end than at the wide angle end,
the rear side lens unit comprises a third lens unit located closer to the object side at the telephoto end than at the wide angle end and having a positive refracting power, the distance between the third lens unit and the second lens unit being smaller at the telephoto end than at the wide angle end, and
the third lens unit satisfies the following condition:
0.01<f3ft<0.16\u2003\u2003(1)
where fl is a focal length of the third lens unit, and ft is a focal length of the entire zoom lens system at the telephoto end;
wherein the zoom lens satisfies the following condition:
1.26<\u03a3D1\u03a3D2<3.00\u2003\u2003(4)
where \u03a3D1 is a thickness of the first lens unit on the optical axis, and \u03a3D2 is a thickness of the second lens unit on the optical axis, the thickness of each lens unit on the optical axis referring to an actual distance from an object side surface of the lens located closest to the object side in that lens unit to an image side surface of the lens located closest to the image side in that lens unit.
3. A zoom lens consisting, in order from an object side thereof, of:
a front side lens unit having a negative refracting power at a wide angle end; and
a rear side lens unit having a positive refracting power at the wide angle end, wherein
the front side lens unit comprises a first lens unit located closest to the object side and having a positive refracting power and a second lens unit located on an image side of the first lens unit and having a negative refracting power, the distance between the first lens unit and the second lens unit being larger at a telephoto end than at the wide angle end,
the rear side lens unit comprises a third lens unit located closer to the object side at the telephoto end than at the wide angle end and having a positive refracting power, the distance between the third lens unit and the second lens unit being smaller at the telephoto end than at the wide angle end, and
the third lens unit satisfies the following condition:
0.01<f3ft<0.16\u2003\u2003(1)
where f3 is a focal length of the third lens unit, and ft is a focal length of the entire zoom lens system at the telephoto end;
wherein the zoom lens satisfies the following conditions:
9<ftfw<50\u2003\u2003(6)
1.1<LtLw<2.0\u2003\u2003(7)
where fW is the focal length of the entire zoom lens system at the wide angle end, Lt is an actual distance, on the optical axis, from the lens surface closest to the object side in the first lens unit to an image plane at the telephoto end, and Lw is an actual distance, on the optical axis, from the lens surface closest to the object side in the first lens unit to the image plane at the wide angle end.
4. A zoom lens consisting, in order from an object side thereof, of:
a front side lens unit having a negative refracting power at a wide angle end; and
a rear side lens unit having a positive refracting power at the wide angle end, wherein
the front side lens unit comprises a first lens unit located closest to the object side and having a positive refracting power and a second lens unit located on an image side of the first lens unit and having a negative refracting power, the distance between the first lens unit and the second lens unit being larger at a telephoto end than at the wide angle end,
the rear side lens unit comprises a third lens unit located closer to the object side at the telephoto end than at the wide angle end and having a positive refracting power, the distance between the third lens unit and the second lens unit being smaller at the telephoto end than at the wide angle end, and
the third lens unit satisfies the following condition:
0.01<f3ft<0.16\u2003\u2003(1)
where f3 is a focal length of the third lens unit, and ft is a focal length of the entire zoom lens system at the telephoto end;
wherein every lens unit included in the zoom lens has an aspheric lens surface.