US5844659A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Opthalmic apparatus for measuring a refractive power of an eye to be examined
Assignee: Nidek Co Ltd
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Filing: 1997-06-16
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Granted: 1998-12-01
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Expires: 2017-06-16
Abstract
Abstract An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus providing an alignment detecting device for detecting an alignment condition of the apparatus corresponding to the eye to be examined by projecting a light so as to form a target onto the eye to be examined and detecting the target, a first judging device for judging whether the alignment condition of up-down/left-right directions is within a predetermined allowable condition based on the detected result of the alignment detecting device, a refractive power temporary measuring device for measuring a temporary refractive power value of the eye to be examined by generating a measurement start signal when it is judged by the first judging device that the alignment condition of up-down/ left-right directions is within the predetermined allowable condition, variable means for varying an allowable condition of working distance based on a measured result of the refractive power temporary measuring device, and a second judging device for judging whether the eye to be examined is arranged within the allowable condition of working distance set by the variable device based on the detected result of the alignment detecting device.
Inventors
- 👤 Naoki Isogai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:02
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/103; A61B3/14; A61B3/15
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
189 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment detecting means for detecting an alignment condition of the apparatus corresponding to the eye to be examined by projecting a light so as to form a target onto the eye to be examined and detecting the target; first judging means for judging whether an alignment condition of up-down/left-right directions is within a predetermined allowable condition based on a detected result of said alignment detecting means; refractive power temporary measuring means for measuring a temporary refractive power value of the eye to be examined by generating a measurement start signal when it is judged by said first judging means that the alignment condition of up-down/ left-right directions is within the predetermined allowable condition; variable means for varying the allowable condition of working distance based on a measured result of said refractive power temporary measuring means; and second judging means for judging whether the eye to be examined is arranged within the allowable condition of working distance set by said variable means based on the detected result of said alignment detecting means.
Claim 2
Dependent Claim
189 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment detecting means for detecting an alignment condition of the apparatus corresponding to the eye to be examined by projecting a light so as to form a target onto the eye to be examined and detecting the target; first judging means for judging whether an alignment condition of up-down/left-right directions is within a predetermined allowable condition based on a detected result of said alignment detecting means; refractive power temporary measuring means for measuring a temporary refractive power value of the eye to be examined by generating a measurement start signal when it is judged by said first judging means that the alignment condition of up-down/ left-right directions is within the predetermined allowable condition; variable means for varying the allowable condition of working distance based on a measured result of said refractive power temporary measuring means; and second judging means for judging whether the eye to be examined is arranged within the allowable condition of working distance set by said variable means based on the detected result of said alignment detecting means.
Claim 3
Dependent Claim
50 words
The ophthalmic apparatus according to claim 1, further comprising allowable condition control means for controlling the allowable condition of working distance which is varied by said variable means such as the allowable condition is to be expanded when the refractive power is a low power compared with a high power.
Claim 4
Dependent Claim
61 words
The ophthalmic apparatus according to claim 1, further comprising memory means for storing a table for setting the working distance necessary for the temporary refractive power value which is obtained by said refractive power temporary measuring means, whereby the allowable condition of working distance being varied by said variable means based on said table which is stored by said memory means.
Claim 5
Dependent Claim
55 words
The ophthalmic apparatus according to claim 1, further comprising calculation means for calculating the working distance necessary for the temporary refractive power value which is obtained by said refractive power temporary measuring means, whereby the allowable condition of working distance being varied by said variable means based on the calculated result by said calculation means.
Claim 6
Dependent Claim
45 words
The ophthalmic apparatus according to claim 1, further comprising actual measurement start signal generating means for generating a measurement start signal for the actual measurement when it is judged by said first and second judging means that the alignment condition fulfills the predetermined allowable condition.
Claim 7
Dependent Claim
159 words
The ophthalmic apparatus according to claim 1, wherein said alignment detecting means includes, first target projection optical system for projecting an target for alignment onto a cornea of the eye to be examined from a visual axial direction of the eye to be examined; first target image detecting means for detecting said first target image formed by said first target projection optical system; second target projection optical system for projecting an target, which has different optical distance up to the eye to be examined, onto the eye; second target image detecting means for detecting second target image formed by said second target projection optical system, whereby the alignment condition of the up-down/left-right directions being judged by said first judging means based on the detected result by said first target image detecting means, and the alignment condition of a toward-away direction being judged by said second judging means based on the detected result by said second target image detecting means.
Claim 8
Dependent Claim
24 words
The ophthalmic apparatus according to claim 6, wherein said first target image detecting means and said second target image detecting means are shared respectively.
Claim 9
Dependent Claim
140 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment means for detecting an alignment condition of the apparatus corresponding to an eye to be examined; refractive power temporary measuring means for measuring a temporary refractive power value after alignment of up-down/left-right directions is completed based on a detected result of said alignment means; variable means for varying an allowable condition of working distance based on a measured data by said refractive power temporary measuring means; detecting means for detecting a distance relation of the apparatus corresponding to the eye to be examined and detecting an alignment condition; and judging means for judging whether the eye to be examined is arranged within a range of allowable condition set by said variable means based on the detected result by said detecting means.
Claim 10
Dependent Claim
140 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment means for detecting an alignment condition of the apparatus corresponding to an eye to be examined; refractive power temporary measuring means for measuring a temporary refractive power value after alignment of up-down/left-right directions is completed based on a detected result of said alignment means; variable means for varying an allowable condition of working distance based on a measured data by said refractive power temporary measuring means; detecting means for detecting a distance relation of the apparatus corresponding to the eye to be examined and detecting an alignment condition; and judging means for judging whether the eye to be examined is arranged within a range of allowable condition set by said variable means based on the detected result by said detecting means.
Claim 11
Dependent Claim
50 words
The ophthalmic apparatus according to claim 8, further comprising allowable condition control means for controlling the allowable condition of working distance which is varied by said variable means such as the allowable condition is to be expanded when the refractive power is a low power compared with a high power.
Claim 12
Dependent Claim
61 words
The ophthalmic apparatus according to claim 8, further comprising memory means for storing a table for setting the working distance necessary for the temporary refractive power value which is obtained by said refractive power temporary measuring means, whereby the allowable condition of working distance being varied by said variable means based on said table which is stored by said memory means.
Claim 13
Dependent Claim
55 words
The ophthalmic apparatus according to claim 8, further comprising calculation means for calculating the working distance necessary for the temporary refractive power value which is obtained by said refractive power temporary measuring means, whereby the allowable condition of working distance being varied by said variable means based on the calculated result by said calculation means.
Claim 14
Dependent Claim
42 words
The ophthalmic apparatus according to claim 8, further comprising actual measurement start signal generating means for generating a measurement start signal for the actual measurement when it is judged by said judging means that the alignment condition fulfills the predetermined allowable condition.
Claim 15
Dependent Claim
151 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment detecting means for detecting an alignment condition of the apparatus corresponding to an eye to be examined; first refractive power measuring means for measuring the refractive power of the eye to be examined based on a detected result by said alignment detecting means; variable means for varying an allowable condition of working distance based on a measured result which is obtained by said first refractive power measuring means; working distance judging means for judging whether the eye to be examined is arranged within a range of allowable condition of working distance set by said variable means based on the detected result of said alignment detecting means; and second refractive power measuring means for measuring the refractive power of the eye to be examined based on the judged result by said judging means.
Claim 16
Dependent Claim
151 words
An ophthalmic apparatus for measuring a refractive power of an eye to be examined, the ophthalmic apparatus comprising: alignment detecting means for detecting an alignment condition of the apparatus corresponding to an eye to be examined; first refractive power measuring means for measuring the refractive power of the eye to be examined based on a detected result by said alignment detecting means; variable means for varying an allowable condition of working distance based on a measured result which is obtained by said first refractive power measuring means; working distance judging means for judging whether the eye to be examined is arranged within a range of allowable condition of working distance set by said variable means based on the detected result of said alignment detecting means; and second refractive power measuring means for measuring the refractive power of the eye to be examined based on the judged result by said judging means.
Claim 17
Dependent Claim
102 words
The ophthalmic apparatus according to claim 13, wherein said alignment detecting means including up-down/left-right directions alignment detecting means for detecting the alignment condition of the up-down/left-right directions in the apparatus corresponding to the eye to be examined; and the apparatus further comprising: up-down/left-right directions judging means for judging whether the alignment condition of the up-down/left-right directions is within the predetermined allowable condition based on the result by said up-down/left-right direction alignment detecting means; and measurement start signal generating means for generating a measurement start signal based on the judged result by said up-down/left-right directions judging means and said working distance judging means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-11-30 | 2002-06-01 | 2002-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-11-30 | 2006-06-01 | 2006-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-11-30 | 2010-06-01 | 2010-12-01 | $7700.00 | Window Closed / Lapsed |