Displacement information detection apparatus, scale used in the apparatus, and drive apparatus using the apparatus

Claim 3

An apparatus according to claim 1, wherein the periodic signal generation diffraction grating and the diffraction grating of the predetermined data recording portion are phase diffraction gratings.

Claim 4

An apparatus according to claim 1, wherein the periodic signal generation diffraction grating and the diffraction grating of the predetermined data recording portion are radial diffraction gratings.

Claim 5

An apparatus according to claim 1, wherein the predetermined data recording portion has recorded origin information of said scale with the diffraction grating.

Claim 6

An apparatus according to claim 4, wherein the predetermined data recording portion has recorded the origin information of said scale as a change in duty or pitch of the diffraction grating.

Claim 7

An apparatus according to claim 1, wherein the predetermined data recording portion has recorded absolute position information of said scale with the diffraction grating.

Claim 8

An apparatus according to claim 6, wherein the predetermined data recording portion has recorded the absolute position information of said scale as a change in duty or pitch of the diffraction grating.

Claim 9

An apparatus according to claim 1, wherein the predetermined data recording portion has recorded origin information of said scale and absolute position information of said scale with the diffraction grating.

Claim 10

A drive control apparatus comprising: a scale arranged on a side of an object of which relative displacement information is to be detected, said scale including a periodic signal generation diffraction grating formed at a predetermined pitch, and a predetermined data recording portion formed independently of the periodic signal generation diffraction grating and for detecting displacement information; a detection unit comprising first and second detection systems, said first detection system irradiating a light beam onto the periodic signal generation diffraction grating to generate diffracted light, said first detection system forming a periodic signal corresponding to a displacement relative to said scale by detecting interference light of the diffracted light generated by the periodic signal generation diffraction grating, and said second detection system optically detecting the predetermined data recording portion; and a control unit for controlling a displacement driving operation of the object on which said scale is arranged, on the basis of detection signals obtained by said first and second detection systems, wherein the predetermined data recording portion also has a diffraction grating.

Claim 11

A drive control apparatus comprising: a scale arranged on a side of an object of which relative displacement information is to be detected, said scale including a periodic signal generation diffraction grating formed at a predetermined pitch, and a predetermined data recording portion formed independently of the periodic signal generation diffraction grating and for detecting displacement information; a detection unit comprising first and second detection systems, said first detection system irradiating a light beam onto the periodic signal generation diffraction grating to generate diffracted light, said first detection system forming a periodic signal corresponding to a displacement relative to said scale by detecting interference light of the diffracted light generated by the periodic signal generation diffraction grating, and said second detection system optically detecting the predetermined data recording portion; and a control unit for controlling a displacement driving operation of the object on which said scale is arranged, on the basis of detection signals obtained by said first and second detection systems, wherein the predetermined data recording portion also has a diffraction grating.

Claim 12

An apparatus according to claim 9, wherein the periodic signal generation diffraction grating and the diffraction grating of the predetermined data recording portion are phase diffraction gratings.

Claim 13

An apparatus according to claim 9, wherein the periodic signal generation diffraction grating and the diffraction grating of the predetermined data recording portion are radial diffraction gratings.

Claim 14

An apparatus according to claim 9, wherein the predetermined data recording portion has recorded origin information of said scale with the diffraction grating.

Claim 15

An apparatus according to claim 12, wherein the predetermined data recording portion has recorded the origin information of said scale as a change in duty or pitch of the diffraction grating.

Claim 16

An apparatus according to claim 9, wherein the predetermined data recording portion has recorded absolute position information of said scale with the diffraction grating.

Claim 17

An apparatus according to claim 14, wherein the predetermined data recording portion has recorded the absolute position information of said scale as a change in duty or pitch of the diffraction grating.

Claim 18

An apparatus according to claim 9, wherein the predetermined data recording portion has recorded origin information of said scale and absolute position information of said scale with the diffraction grating.

Claim 19

A displacement information detection scale to be arranged on a side of an object of which relative displacement information is to be detected, comprising: a periodic signal generation diffraction grating formed at a predetermined pitch to generate diffracted light which is to be detected in an interference state upon irradiation of a light beam from an external portion, a periodic signal corresponding to a displacement of said scale relative to the external portion being obtained by detecting the diffracted light in the interference state; and a predetermined data recording portion which is formed independently of said periodic signal generation diffraction grating so as to be optically detected by the external portion for the purpose of relative displacement information detection of said scale, said predetermined data recording portion also having a diffraction grating.

Claim 20

A displacement information detection scale to be arranged on a side of an object of which relative displacement information is to be detected, comprising: a periodic signal generation diffraction grating formed at a predetermined pitch to generate diffracted light which is to be detected in an interference state upon irradiation of a light beam from an external portion, a periodic signal corresponding to a displacement of said scale relative to the external portion being obtained by detecting the diffracted light in the interference state; and a predetermined data recording portion which is formed independently of said periodic signal generation diffraction grating so as to be optically detected by the external portion for the purpose of relative displacement information detection of said scale, said predetermined data recording portion also having a diffraction grating.

Claim 21

A scale according to claim 17, wherein said periodic signal generation diffraction grating and the diffraction grating of said predetermined data recording portion are phase diffraction gratings.

Claim 22

A scale according to claim 17, wherein said periodic signal generation diffraction grating and the diffraction grating of said predetermined data recording portion are radial diffraction gratings.

Claim 23

A scale according to claim 17, wherein said predetermined data recording portion has recorded origin information of said scale with the diffraction grating.

Claim 24

A scale according to claim 20, wherein said predetermined data recording portion has recorded the origin information of said scale as a change in duty or pitch of the diffraction grating.

Claim 25

A scale according to claim 17, wherein said predetermined data recording portion has recorded absolute position information of said scale with the diffraction grating.

Claim 26

A scale according to claim 22, wherein said predetermined data recording portion has recorded the absolute position information of said scale as a change in duty or pitch of the diffraction grating.

Claim 27

A scale according to claim 17, wherein the predetermined data recording portion has recorded origin information of said scale and absolute position information of said scale with the diffraction grating.