Patent US4533222A successfully refreshed from Google Patents.
US4533222A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Eye examining instrument
Assignee: Canon Inc
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Filing: 1984-07-20
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Granted: 1985-08-06
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Expires: 2004-07-20
Abstract
Abstract An eye examining instrument comprises examining means disposed to project an examining light to and receive the light from the eye of a person to be examined; a casing for encasing said examining means; a beam splitter disposed on the outside of said casing for directing the examining light to the eye to be examined, said beam splitter having sufficient width to allow both eyes of the person to be examined to see a fixation object and being directly opposed to the eye to be examined; and a cover connected with said casing for preventing any undesirable light from coming into said beam splitter.
Inventors
- 👤 Yasuyuki Ishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:38
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
236 words
An eye examining instrument comprising: examining means, for measuring a refraction error of each eye of a person to be examined, said examining means projecting an invisible examining light to be directed to the examined eye and receiving the invisible examining light reflected from the examined eye; a casing containing said examining means formed with an opening that opens upwardly through which the invisible examining light is projected to be directed to the examined eye and through which the invisible examining light is received from the examined eye; beam splitting means disposed on the outside of said casing for directing said invisible examining light to the examined eye and permitting the person being examined to view a fixation object spaced from said casing, said beam splitting means including a mirror that transmits visible light and reflects the invisible examining light, said mirror having a sufficient width to allow both eyes of the person to be examined to view simultaneously the fixation object while either of the person's eyes can be examined by moving said instrument laterally with respect to the eyes; and shielding means for covering said beam splitting means so as to shield it from undesirable light but for allowing the eye to view the fixation object through said beam splitting means, said shielding means having a top surface and two side surfaces, said side surfaces transmitting visible light, and said top surface being opaque.
Claim 2
Dependent Claim
236 words
An eye examining instrument comprising: examining means, for measuring a refraction error of each eye of a person to be examined, said examining means projecting an invisible examining light to be directed to the examined eye and receiving the invisible examining light reflected from the examined eye; a casing containing said examining means formed with an opening that opens upwardly through which the invisible examining light is projected to be directed to the examined eye and through which the invisible examining light is received from the examined eye; beam splitting means disposed on the outside of said casing for directing said invisible examining light to the examined eye and permitting the person being examined to view a fixation object spaced from said casing, said beam splitting means including a mirror that transmits visible light and reflects the invisible examining light, said mirror having a sufficient width to allow both eyes of the person to be examined to view simultaneously the fixation object while either of the person's eyes can be examined by moving said instrument laterally with respect to the eyes; and shielding means for covering said beam splitting means so as to shield it from undesirable light but for allowing the eye to view the fixation object through said beam splitting means, said shielding means having a top surface and two side surfaces, said side surfaces transmitting visible light, and said top surface being opaque.
Claim 3
Dependent Claim
44 words
An eye examining instrument according to claim 1 wherein said side surfaces are spaced by a distance sufficient so that said side surfaces do not interfere with the field of view of the fixation object of both eyes of a person to be examined.
Claim 4
Dependent Claim
19 words
An eye examining instrument according to claim 1, wherein said mirror is disposed directly opposed to the examined person.
Claim 5
Dependent Claim
22 words
An eye examining instrument according to claim 1, wherein said mirror has a multilayer interferential film applied onto its parallel plane plate.
Claim 6
Dependent Claim
24 words
An eye examining instrument according to claim 1, which further comprises a second fixation object supported on said casing for fixing the examined eye.
Claim 7
Dependent Claim
36 words
An eye examining instrument according to claim 1, wherein said examining means includes a video camera, sensitive to visible light, for taking an image, through said opening, of an interior of the eye to be examined.
Claim 8
Dependent Claim
27 words
An eye examining instrument according to claim 1, wherein said examining means includes an objective lens disposed in said opening and having a vertically extending optical axis.
Claim 9
Dependent Claim
191 words
An eye examining instrument comprising: examining means, for measuring a refraction error of each eye of a person to be examined, said examining means projecting an invisible examining light to be directed to the examined eye and receiving the invisible examining light reflected from the examined eye; a casing containing said examining means formed with an opening that opens upwardly through which the invisible examining light is projected to be directed to the examined eye and through which the invisible examining light is received from the examined eye; beam splitting means disposed on the outside of said casing for directing said invisible examining light to the examined eye and permitting the person being examined to view a fixation object spaced from said casing, said beam splitting means transmitting visible light and reflecting the invisible examining light; and shielding means for covering said beam splitting means so as to shield it from undesirable light but for allowing the eye to view a fixation object through said beam splitting means, said shielding means having a top surface and two side surfaces, said side surfaces transmitting visible light, and said top surface being opaque.
Claim 10
Dependent Claim
191 words
An eye examining instrument comprising: examining means, for measuring a refraction error of each eye of a person to be examined, said examining means projecting an invisible examining light to be directed to the examined eye and receiving the invisible examining light reflected from the examined eye; a casing containing said examining means formed with an opening that opens upwardly through which the invisible examining light is projected to be directed to the examined eye and through which the invisible examining light is received from the examined eye; beam splitting means disposed on the outside of said casing for directing said invisible examining light to the examined eye and permitting the person being examined to view a fixation object spaced from said casing, said beam splitting means transmitting visible light and reflecting the invisible examining light; and shielding means for covering said beam splitting means so as to shield it from undesirable light but for allowing the eye to view a fixation object through said beam splitting means, said shielding means having a top surface and two side surfaces, said side surfaces transmitting visible light, and said top surface being opaque.
Claim 11
Dependent Claim
25 words
An eye examining instrument according to claim 8, wherein said beam splitting means comprises a mirror and is disposed directly opposed to the examined person.
Claim 12
Dependent Claim
22 words
An eye examining instrument according to claim 9, wherein said mirror has a multilayer interferential film applied onto its parallel plane plate.
Claim 13
Dependent Claim
24 words
An eye examining instrument according to claim 8, which further comprises a second fixation object supported on said casing for fixing the examined eye.
Claim 14
Dependent Claim
36 words
An eye examining instrument according to claim 8, wherein said examining means includes a video camera, sensitive to visible light, for taking an image, through said opening, of an interior of the eye to be examined.
Claim 15
Dependent Claim
27 words
An eye examining instrument according to claim 8, wherein said examining means includes an objective lens disposed in said opening and having a vertically extending optical axis.
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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) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |