Patent US3801188A successfully refreshed from Google Patents.
US3801188A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and means for testing the colour discrimination in vision
Assignee: TINTOMETER Ltd
•
Filing: 1972-07-11
•
Granted: 1974-04-02
•
Expires: 1992-07-11
Abstract
Abstract A method and apparatus for determining the colour discrimination of the vision of a subject in which light of a predetermined reference colour is compared with a plurality of lights of different test colours, one of which is preferably identical with the reference colour, and diluting the coloured lights with a diluting colour, and changing the relative intensity of dilution therebetween and measuring the value of said relative dilution when the subject attempts to match the reference light with one of the test colours.
Inventors
- 👤 R Hunt
- 👤 S Dain
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 05:49
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/02; A61B3/06; A61B3/066
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
169 words
A method of determining the colour discrimination of the vision of a subject comprising: viewing simultaneously a source of light of a reference colour of predetermined colour and a plurality of sources of light of different test colours of a variety of predetermined colours, one of which is preferably identical in colour with the colour of the source of light of the reference colour; diluting the source of light of reference colour and the plurality of sources of light of different test colours with light of the same colour; changing the relative intensity of the diluting light between (a) the source of light of reference colour and (b) the plurality of sources of light of different test colours; and indicating the value of said relative dilution, whereby the characteristic of said discrimination can be ascertained by the subject attempting to match the light received from the source of light of reference colour and the light received from one of the plurality of sources of light from the test colours.
Claim 2
Independent Claim
169 words
A method of determining the colour discrimination of the vision of a subject comprising: viewing simultaneously a source of light of a reference colour of predetermined colour and a plurality of sources of light of different test colours of a variety of predetermined colours, one of which is preferably identical in colour with the colour of the source of light of the reference colour; diluting the source of light of reference colour and the plurality of sources of light of different test colours with light of the same colour; changing the relative intensity of the diluting light between (a) the source of light of reference colour and (b) the plurality of sources of light of different test colours; and indicating the value of said relative dilution, whereby the characteristic of said discrimination can be ascertained by the subject attempting to match the light received from the source of light of reference colour and the light received from one of the plurality of sources of light from the test colours.
Claim 3
Dependent Claim
38 words
A method as claimed in claim 1 in which the step of diluting is constituted by diluting the source of light of reference colour and the plurality of sources of light of different test colours with white light.
Claim 4
Dependent Claim
36 words
A method as claimed in claim 1 in which the intrinsic intensity of the source of light of reference colour is variable relative to the intrinsic intensity of the source of light of the test colours.
Claim 5
Dependent Claim
43 words
A method as claimed in claim 1 in which the viewing step is constituted by transmitting light of selected predetermined colour from a common lamp which generates polychromatic light through a plurality of transparent coloured members to provide said source and said sources.
Claim 6
Dependent Claim
142 words
Apparatus for determining the colour discrimination of the vision of a subject comprising a housing, an illuminating lamp in the housing, a first diffusing means for producing a uniform field of diffused light from said lamp in a first plane, a support means mounted for movement in a plane parallel to said first plane, windows in the support means each provided with transparent means of different colours for the passage of diffused light from said first plane, a second diffusing means for producing a uniform field of diffused light from said lamp in a second plane, optical means for varying the relative intensity of diffused light from the two planes, optical means for viewing the light from the two planes superimposed the one upon the other, and indicating means for indicating the relative intensity of the diffused light from the two planes.
Claim 7
Dependent Claim
142 words
Apparatus for determining the colour discrimination of the vision of a subject comprising a housing, an illuminating lamp in the housing, a first diffusing means for producing a uniform field of diffused light from said lamp in a first plane, a support means mounted for movement in a plane parallel to said first plane, windows in the support means each provided with transparent means of different colours for the passage of diffused light from said first plane, a second diffusing means for producing a uniform field of diffused light from said lamp in a second plane, optical means for varying the relative intensity of diffused light from the two planes, optical means for viewing the light from the two planes superimposed the one upon the other, and indicating means for indicating the relative intensity of the diffused light from the two planes.
Claim 8
Dependent Claim
48 words
Apparatus as claimed in claim 5 in which the diffusing means for producing a uniform field of diffused light is a box like channel with open ends with mirrored inner surfaces and a diffusing screen in said plane at the opposite end of the channel to the lamp.
Claim 9
Dependent Claim
41 words
Apparatus as claimed in claim 6 in which there are two channels which are positioned parallel to one another and the plane of diffused light of one said channel is co-extensive of the plane of diffused light of the other channel.
Claim 10
Dependent Claim
50 words
Apparatus as claimed in claim 5 in which the support means is opaque and is disc like in form and has a plurality of windows therein arranged in a regular pattern, one of which serves as a source of reference colour while the remainder serve as sources of test colours.
Claim 11
Dependent Claim
40 words
Apparatus as claimed in claim 7 in which the lamp is mounted at the end of the channel remote from the plane of diffused light and the light from the lamp is directed along each channel by a tilted mirror.
Claim 12
Dependent Claim
55 words
Apparatus as claimed in claim 9 in which the optical means for varying the relative intensity of diffused light from the two planes is a plate of varying opacity thereover which is positioned across the openings in the channels adjacent the lamp and movable to change the relative intensity of light passing down the channels.
Claim 13
Dependent Claim
75 words
Apparatus as claimed in claim 5 in which the means for viewing the light from the two planes superImposed one one upon the other, are a plane mirror adjacent said first plane and set at an angle thereto, and a plane sheet of transparent material adjacent said second plane and acting as a partial mirror, and set at an angle thereto, the image reflected in the mirror being viewed through the sheet of transparent material.
Claim 14
Dependent Claim
34 words
Apparatus as claimed in claim 8 in which there is provided behind the window which serves as a source of reference colour optical means for varying the intensity of light transmitted by said window.
References Cited (Backward Citations)
US2528513A
Cited
FR1043216A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |