US5136558A — Two axis electromagnetic actuator

Claim 1

Independent Claim 148 words

An actuator, comprising: a base; an objective lensholder, movably mounted on said base; an objective lens mounted on said lensholder; a pair of permanent magnets, secured to said lensholder on laterally opposed sides, each of said pair of permanent magnets having a direction of magnetization; a first coil, positioned on said base to create a first electromagnetic field which interacts with the magnetization of said permanent magnets to move said lensholder in a first direction relative to said base; and a second coil having a central axis, positioned on said base to create a second electromagnetic field which interacts with the magnetization of said permanent magnets to move said lensholder in a second direction relative to said base, substantially perpendicular to said first direction, wherein said central axis of said second coil is substantially perpendicular to each of said directions of magnetization of said pair of permanent magnets.

Claim 2

Dependent Claim 148 words

An actuator, comprising: a base; an objective lensholder, movably mounted on said base; an objective lens mounted on said lensholder; a pair of permanent magnets, secured to said lensholder on laterally opposed sides, each of said pair of permanent magnets having a direction of magnetization; a first coil, positioned on said base to create a first electromagnetic field which interacts with the magnetization of said permanent magnets to move said lensholder in a first direction relative to said base; and a second coil having a central axis, positioned on said base to create a second electromagnetic field which interacts with the magnetization of said permanent magnets to move said lensholder in a second direction relative to said base, substantially perpendicular to said first direction, wherein said central axis of said second coil is substantially perpendicular to each of said directions of magnetization of said pair of permanent magnets.

Claim 3

Dependent Claim 25 words

An actuator, as defined by claim 1, wherein said magnets are arranged such that said direction of magnetization of said magnets is collinear but opposite.

Claim 4

Dependent Claim 33 words

An actuator, as defined by claim 1, further comprising: a pair of flexures, mounted to said base on laterally opposed sides, said flexures constructed and arranged to suspend said lensholder from said base.

Claim 5

Dependent Claim 24 words

An actuator, as defined by claim 3, wherein said flexures move in a parallel relationship to one another, to enable movement of said lensholder.

Claim 6

Dependent Claim 15 words

An actuator, as defined by claim 3, further comprising a mirror, positioned between said flexures.

Claim 7

Dependent Claim 40 words

An actuator, as defined by claim 5, wherein said mirror is oriented such that light entering said actuator is reflected by said mirror toward said objective lensholder, in a direction substantially perpendicular to the direction of said incident laser light.

Claim 8

Dependent Claim 23 words

An actuator, as defined by claim 5, wherein said mirror is secured to a rod which remains stationary with respect to said base.

Claim 9

Dependent Claim 21 words

An actuator, as defined by claim 1, wherein said base serves as a heat sink for said first and second coils.

Claim 10

Dependent Claim 22 words

An actuator, as defined by claim 1, wherein said lensholder comprises a plurality of vacant faces through which light may be conducted.

Claim 11

Dependent Claim 12 words

An actuator, as defined by claim 1, further comprising a positioning sensor.

Claim 12

Dependent Claim 76 words

An actuator, as defined by claim 10, wherein said positioning sensor comprises: a detector, mounted to said base; and a light emitting diode, mounted to said base, laterally opposed from said detector, said diode constructed and arranged to emit light through said lensholder and onto said detector, wherein the light impingent on said detector causes said detector to produce an output signal which is indicative of the positioning of said lensholder with respect to said base.

Claim 13

Dependent Claim 14 words

An actuator, as defined by claim 11, wherein said detector comprises a quad diode.

Claim 14

Dependent Claim 26 words

An actuator, as defined by claim 11, wherein said detector comprises a two-way position sensitive detector which detects the position of said lensholder in two directions.

Claim 15

Dependent Claim 27 words

An actuator, as defined by claim 10, wherein said lensholder further comprises a flange having a vertical slot, said slot positioned in alignment with said positioning sensor.

Claim 16

Dependent Claim 82 words

An actuator, as defined by claim 14, wherein said positioning sensor further comprises: a detector, mounted to said base collinear with said vertical slot of said flange; and a light emitting diode, mounted to said base, laterally opposed from said detector, said diode constructed and arranged to emit roughly collimated light through said vertical slot of said flange and onto said detector, wherein the amount and position of said collimated light on said detector is indicative of the positioning of said lensholder.

Claim 17

Dependent Claim 15 words

An actuator, as defined by claim 15, wherein said detector comprises a dual split diode.

Claim 18

Dependent Claim 15 words

An actuator, as defined by claim 15, wherein said detector comprises a position sensitive detector.

Claim 19

Dependent Claim 146 words

A two axis electromagnetic actuator, comprising; a base; a flexure, fixed to said base and movable with respect to said base; a lensholder, mounted on said flexure; an objective lens mounted on said lensholder defining an optical axis; a permanent magnet having a direction of magnetization, secured to said lensholder; a first coil, secured to said base, said first coil positioned to create a magnetic field which urges said permanent magnet and thus said lensholder to move in a first direction; and a second coil having a central axis secured to said base, said second coil positioned to create a magnetic field which urges said permanent magnet and thus said lensholder to move in a second direction, different from said first direction collinear with said optical axis, said central axis of said second coil being substantially perpendicular to said direction of magnetization of said permanent magnet.

Claim 20

Dependent Claim 146 words

A two axis electromagnetic actuator, comprising; a base; a flexure, fixed to said base and movable with respect to said base; a lensholder, mounted on said flexure; an objective lens mounted on said lensholder defining an optical axis; a permanent magnet having a direction of magnetization, secured to said lensholder; a first coil, secured to said base, said first coil positioned to create a magnetic field which urges said permanent magnet and thus said lensholder to move in a first direction; and a second coil having a central axis secured to said base, said second coil positioned to create a magnetic field which urges said permanent magnet and thus said lensholder to move in a second direction, different from said first direction collinear with said optical axis, said central axis of said second coil being substantially perpendicular to said direction of magnetization of said permanent magnet.

Claim 21

Dependent Claim 22 words

An actuator, as defined by claim 18, wherein said lensholder has at least four vacant faces through which light may be conducted.

Claim 22

Dependent Claim 22 words

An actuator, as defined by claim 18, further comprising a mirror, said mirror positioned within said lensholder, for reflecting incoming laser light.

Claim 23

Dependent Claim 32 words

An actuator, as defined by claim 20, wherein said mirror is oriented such that said laser light is reflected in a direction substantially perpendicular to the direction of said incoming laser light.

Claim 24

Dependent Claim 23 words

An actuator, as defined by claim 20, wherein said mirror is secured to a rod which remains stationary with respect to said base.

Claim 25

Dependent Claim 41 words

An actuator, as defined by claim 18, wherein said first coil has a central axis and is mounted to said base such that said central axis of said first coil is substantially collinear with said direction of magnetization of said magnet.

Claim 26

Dependent Claim 39 words

An actuator, as defined by claim 18, wherein first coil has a central axis and is mounted on said base such that said central axis of said first coil is offset from the center of magnetization of said magnet.

Claim 27

Dependent Claim 114 words

A two axis electromagnetic actuator, comprising: a base; an objective lensholder, movably mounted on said base; a pair of permanent magnets, secured to said lensholder on laterally opposed sides, each of said permanent magnets having a direction of magnetization; a first pair of coils, secured to said base on laterally opposed sides, each of said first pair of coils having a central axis which is substantially collinear with the direction of magnetization of said permanent magnets; and a second pair of coils, secured to said base on laterally opposed sides, each of said second pair of coils having a central axis which is substantially perpendicular to the direction of magnetization of said permanent magnets.

Claim 28

Dependent Claim 114 words

A two axis electromagnetic actuator, comprising: a base; an objective lensholder, movably mounted on said base; a pair of permanent magnets, secured to said lensholder on laterally opposed sides, each of said permanent magnets having a direction of magnetization; a first pair of coils, secured to said base on laterally opposed sides, each of said first pair of coils having a central axis which is substantially collinear with the direction of magnetization of said permanent magnets; and a second pair of coils, secured to said base on laterally opposed sides, each of said second pair of coils having a central axis which is substantially perpendicular to the direction of magnetization of said permanent magnets.

Claim 29

Dependent Claim 31 words

A two axis electromagnetic actuator, as defined by claim 25, wherein said central axes of said first pair of coils are offset from the center of magnetization of said permanent magnets.

Claim 30

Dependent Claim 46 words

A two axis electromagnetic actuator, as defined by claim 25, further comprising: a pair of flexures, mounted to said base on laterally opposed sides, said flexures constructed and arranged to suspend said lensholder within said base and enable movement of said lensholder relative to said base.

Claim 31

Dependent Claim 18 words

A two axis electromagnetic actuator, as defined by claim 27, further comprising a mirror, positioned between said flexures.

Claim 32

Dependent Claim 41 words

A two axis electromagnetic actuator, as defined by claim 28, wherein said mirror is oriented such that light entering said actuator is reflected by said mirror, toward said objective lensholder, in a direction substantially perpendicular to the direction of said light.

Claim 33

Dependent Claim 26 words

A two axis electromagnetic actuator, as defined by claim 28, wherein said mirror is secured to a rod which remains stationary with respect to said base.

Claim 34

Dependent Claim 21 words

A two axis electromagnetic actuator, as defined by claim 25, wherein said base serves as a heat sink for said coils.

Claim 35

Dependent Claim 15 words

A two axis electromagnetic actuator, as defined by claim 25, further comprising a positioning sensor.

Claim 36

Dependent Claim 26 words

A two axis electromagnetic actuator, as defined by claim 26, wherein said objective lensholder has at least four vacant faces through which light may be conducted.

Claim 37

Dependent Claim 158 words

A two axis actuator alignment system, comprising: an objective lens defining an optical axis; a movable component on which said objective lens is mounted, said movable component having a first aperture through which light may be transmitted and a second aperture, substantially in alignment with said first aperture, such alignment of said first aperture and said second aperture being transverse to said optical axis; a base, said base being stationary with respect to said movable component; a light source, mounted to said base, said light source capable of emitting light toward said apertures disposed within said movable component; and a light sensitive detector, mounted to said base on a side laterally opposed from said light source, said detector responsive to light transmitted through said apertures in said movable component, said detector constructed and arranged to generate an output signal which is indicative of the position of said movable component with respect to said base in two axial directions.

Claim 38

Dependent Claim 158 words

A two axis actuator alignment system, comprising: an objective lens defining an optical axis; a movable component on which said objective lens is mounted, said movable component having a first aperture through which light may be transmitted and a second aperture, substantially in alignment with said first aperture, such alignment of said first aperture and said second aperture being transverse to said optical axis; a base, said base being stationary with respect to said movable component; a light source, mounted to said base, said light source capable of emitting light toward said apertures disposed within said movable component; and a light sensitive detector, mounted to said base on a side laterally opposed from said light source, said detector responsive to light transmitted through said apertures in said movable component, said detector constructed and arranged to generate an output signal which is indicative of the position of said movable component with respect to said base in two axial directions.

Claim 39

Dependent Claim 17 words

A positional detection system, as defined by claim 34, wherein said detector comprises a position sensitive detector.

Claim 40

Dependent Claim 15 words

positional detection system, as defined by claim 34, wherein said detector comprises a quad diode.

Claim 41

Dependent Claim 241 words

A two axis electromagnetic actuator, comprising: a base; an objective lensholder, movably mounted on said base; first and second permanent magnets, secured to said lensholder on laterally opposed sides, each of said permanent magnets having a center of magnetization which corresponds to a north pole facing away from said lensholder, said north poles of said permanent magnets being coaxial; a first focus coil secured to said base, above said lensholder, said first coil having a central axis substantially perpendicular to said center of magnetization of said permanent magnets; a second focus coil secured to said base, laterally opposed from said first focus coil, said second focus coil having a central axis coaxial with said central axis of said first focus coil, said first and second coils constructed and arranged to attract and repel said permanent magnets along a focus direction when energized; a first tracking coil secured to said base, adjacent said first permanent magnet, said first tracking coil having a central axis which is substantially collinear with said center of magnetization of said permanent magnets; and a second tracking coil secured to said base, adjacent said second permanent magnet and laterally opposed from said first tracking coil, said second tracking coil having a central axis which is substantially coaxial with said central axis of said first tracking coil, said first and second tracking coils constructed and arranged to attract and repel said permanent magnets along a tracking direction when energized.

Claim 42

Dependent Claim 241 words

A two axis electromagnetic actuator, comprising: a base; an objective lensholder, movably mounted on said base; first and second permanent magnets, secured to said lensholder on laterally opposed sides, each of said permanent magnets having a center of magnetization which corresponds to a north pole facing away from said lensholder, said north poles of said permanent magnets being coaxial; a first focus coil secured to said base, above said lensholder, said first coil having a central axis substantially perpendicular to said center of magnetization of said permanent magnets; a second focus coil secured to said base, laterally opposed from said first focus coil, said second focus coil having a central axis coaxial with said central axis of said first focus coil, said first and second coils constructed and arranged to attract and repel said permanent magnets along a focus direction when energized; a first tracking coil secured to said base, adjacent said first permanent magnet, said first tracking coil having a central axis which is substantially collinear with said center of magnetization of said permanent magnets; and a second tracking coil secured to said base, adjacent said second permanent magnet and laterally opposed from said first tracking coil, said second tracking coil having a central axis which is substantially coaxial with said central axis of said first tracking coil, said first and second tracking coils constructed and arranged to attract and repel said permanent magnets along a tracking direction when energized.

Claim 43

Dependent Claim 38 words

A two axis electromagnetic actuator, as defined by claim 37, wherein said first and second tracking coils are mounted to said base such that their center axes are coaxial with said center of magnetization of said permanent magnets.

Claim 44

Dependent Claim 38 words

A two axis electromagnetic actuator, as defined by claim 37, wherein said first and second tracking coils are mounted to said base such that their central axes are offset from said center of magnetization of said permanent magnets.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1995-08-04	1996-02-03	1996-08-04	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1999-08-04	2000-02-03	2000-08-04	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2003-08-04	2004-02-03	2004-08-04	$7700.00	Window Closed / Lapsed

Two axis electromagnetic actuator

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