CA1170825A

CA1170825A - Lens inspection support

Info

Publication number: CA1170825A
Application number: CA000393945A
Authority: CA
Inventors: Warren J. Heath
Original assignee: Warner Lambert Technologies Inc
Current assignee: Warner Lambert Technologies Inc
Priority date: 1981-02-25
Filing date: 1982-01-12
Publication date: 1984-07-17
Also published as: JPS57154031A; FR2500644A1; FR2500644B1; GB2093605A; GB2093605B; DE3206316A1

Abstract

LENS INSPECTION SUPPORT

ABSTRACT OF THE DISCLOSURE

A device which facilitates positioning a contact lens on a support is disclosed. The device includes a member which alternately lifts the lens off the pedestal and deposits the lens on the pedestal to move the lens optical axis in to coincidence with the pedestal axis. Rapid and accurate positioning is accomplished independent of operator dexterity and lenses of all parameters are accepted without modification.

Description

S

This invention relates to devices for supporting a contact lens for optical inspection and more particularly for rapidly and universally centering the lens independent of operator dexterity.
Discussion of the Prior Art-U.S. Patent No. 3,985,445, issued October 12, 1976to Tagnon. Tagnon discloses a plurality of cups for holding and delivering a lens to a test instrument for inspection.
Each cup is designed to hold a lens of a single size and center the lens as it is delivered to the instrument.
ThereEore, the lens diameter must be known before the correct cup can be selected. Alternatively, Tagnon, in the preferred embodiment, teaches a holder with micrometer positioning screws for moving the lens after it is positioned in the holder.
Applicant's Canadian Patent No. 1,149,338, issued July 5, 1983, discloses an improved device for transporting and positioning a contact lens while it is immersed in a liquid. While the device eliminates the need for the plurality of transporting devices required by Tagnon, centering the lens, rcquires the operator to exercise care and manual dexterity.
It is an object of the present invention to provide a device capable of centering all contact lenses without relying on operator dexterity.
It is another object of the present invention to provide a device for rapidly positioning immersed contact lenses for optical testing.

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~ :~ 7( ~Z5 It is still another object of the present invention to rapidly center an immersed contact lens on a pedestal for testing independent of operator dexterity or lens parameters.

BRIEF DESCRIPTION OF THE PRESENT
INVENTION AND DRAWINGS
The present invention is used in a contact lens inspection holder having a pedestal for supporting a contact lens by the posterior surface, and a container for maintaining the lens immersed in a liquid. The invention relates to the improvement comprising a centering means for facilitating the alignment of the lens axis with the pedestal axis independent of operator dexterity, the centering means being adapted to accommodate lenses of varying diameters and curves without exchange or substitution of structural , components.
The device of the present invention has a vertically displaceable member with an inwardly and downwardly tapering top surface to move a contact lens into axial coincidence with a support pedestal. When the member is raised, the tapering surface shifts the lens into alignment and when lowered, the lens is supported above the taperin~ surface by the pedestal. The centering device is universally useful on soft contact lenses independent of lens parameters.
Fig. 1 is a top plan view of an embodiment of the present invention;
Fig. 2 is a side plan view, partly in section, of the embodiment of Fig. l; and Fig. 3 is a left side plan view in section.

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Referring to Figs. 1 and 2, base 1 has a vertically extending wall 3 forming a container with recess 5 for a liquid (not shown). Preferably the liquid is a buffered saline such as that used to store contact lenses. Hollow pedestal 7 extends upwardly near one end of base 1 and has window 9 sealing the top and providing a planar window for transmitting and reflecting light. Member 11 has a central bore 13 adapted to cooperate with pedestal 7 to locate member 11 . . .

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~na permit it to slide up and down. Slide 15 has a ?air of fingers 17 located by grooves 19 and slidable therealong. Downwardly tapering eZges 21 on fingers 17 su?port member 11 by downwardly tapering bottom surface 23.
Downwardly and inwardly tapering surfaces 25a, 25b and 25c in member 11 are seperated by notches 27a, 27b and 27c, which act as fluid passages around contact lens L when it moves through the liquid in recess S.
Vertical grooves ~9a, 29b and 29c similarly provide passages for the liquid as member 11 is moved.
Referring now to Figure 3, as slide 15 is moved to the right, edges 21 move across bottom surface 23 lowering member 11. As member 11 moves down, lens L
contacts window g and is supported thereby. Cover 31 rests on ledges 33. When positioned to the left (Fig. 1), an access for inserting or removing contact lens L is provided. When positioned to the right the cover contacts the liquid surface above tne lens to prevent disturbance of lens L when resting on pedestal 7 and to provide a uniform smooth surface in contact with the liquid in recess 5 for light transmitted through window 35. Depression 37 provides a gripping means to assist sliding cover 31 back and forth.
To use the device, a contact lens is placed under the liquid surface and in contact with surfaces 25a, 25b and 25c and cover 31 is then slia over member 11.
Slide 15 is moved back and forth several times and then left in the position shown in Fig. 3. This will center a lens of any parameter, since, if the lens is off center before slide 15 is moved, it will settle into a tilted (with respect to horizontal) position on pedestal 7 as member 11 is lo~ered.
As member 11 is raised by movement of slide 15, initial contact by member 11 will be with the low edge of the lens. Continued elevation o, member 11 will cause one of sloping surfaces 25a, 2,~ or 25c to shift the lens into axial aligmnent with pedestal 7. Elevation of member 11 will cease to shift the lens as soon as alignment occurs, since the edge of the lens will be in uniform contact with the corresponding part of each of surfaces 25a, 25b and 25c. Passages 27a, 27b and 27c are important because they prevent liquid from being ~rapped under the lens which would cause the lens to "float" as member 11 is lowered.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a contact lens inspection holder having a pedestal for supporting a contact lens by the posterior surface, and a container for maintaining the lens immersed in a liquid, the improvement comprising a centering means for facilitating the alignment of the lens axis with the pedestal axis independent of operator dexterity, said centering means being adapted to accommodate lenses of varying diameters and curves without exchange or substitution of structural components.

2. In a contact lens inspection holder having a pedestal for supporting a contact lens by the posterior surface, and a container for maintaining the lens immersed in a liquid, the improvement comprising a centering means, said centering means includes a vertically slidable member having a normal position and an elevated position, said member having a top end portion extending inwardly and downwardly, said top end portion being spaced from the lens edge when said member is in the normal position and supporting the lens by its edge when said member is in the elevated position.

3. The improvement of claim 2 further including an elongated member slidably mounted in the container, said elongated member having an inclined surface adjacent one end and said inclined surface being adapted to raise said vertically slidable member from the normal position to the elevated position.

4. The improvement of claim 3 wherein said inclined surface is planar and said vertically slidable member has an inclined-planar, bottom portion adapted to engage said inclined surface.

5. The improvement of claim 4 wherein said elongated member is manually operable.

6. The improvement of claim 2 wherein the container has an internal cylindrical, vertical wall extending coaxial to said pedestal and said slidable member has a complementary, exterior wall, said vertical and exterior walls cooperating to guide said slidable member along a substantially vertical path during movement between said normal and elevated positions and said top portion is a frusto-conical surface.

7. The improvement of claim 3 wherein the container has an internal cylindrical, vertical wall extending coaxial to said pedestal and said slidable member has a complementary, exterior wall, said vertical and exterior walls cooperating to guide said slidable member along a substantially vertical path during movement between said normal and elevated positions and said top portion is a frusto-conical surface.

8. The improvement of claim 6 wherein said frusto-conical surface has a plurality of notches.

9. The improvement of claim 7 wherein said frusto-conical surface has a plurality of notches.

10. The improvement of claim 1 further including a cover to provide a smooth optical interface with the liquid.