Method and apparatus for detecting mouldings in a package

• US 20010009561A1
• Filed: 11/29/2000
• Published: 07/26/2001
• Est. Priority Date: 12/03/1999
• Status: Active Grant

• Current Assignee: Alcon Incorporated
• Original Assignee: Novartis Ag
• Inventors: Biel, Roger
• Granted Patent: US 6,471,396 B2
• Time in Patent Office: Days
• US Class Current: 374/10
• CPC Class Codes: G01N 21/9508 Capsules; Tablets
• CPC Class Codes: G01N 25/72 Investigating presence of flaws

Abstract

The invention relates to a method and a device for registering the presence of an ophthalmic moulding consisting of a biocompatible polymeric material, especially an ophthalmic lens, particularly a contact lens, in a package. The invention solves the problem through the use of an IR camera. Packages containing a moulding, especially a contact lens, have a change in their temperature distribution compared with a package without a contact lens. By evaluating the temperature difference, it is possible to determine whether or not there is a contact lens in a package. In particular, by using the detecting method according to the invention, one can determine whether there is a contact lens in the package directly after the filling procedure.

Claims

1. Method for detecting mouldings consisting of a biocompatible polymeric material, especially ophthalmic lenses, particularly contact lenses, in a blister package, whereby the package is open, characterised in that the temperature of a package with a moulding is measured and compared with the temperature measurement of a package without a moulding, the difference between the two measurements being used to detect a moulding.

2. Method according to

claim 1

, in which local temperature measurement takes place.

3. Method according to

claim 1

or

2

, in which an infrared line camera is used to detect the temperature.

4. Method according to one or more of

claims 1

to

3

, in which the package is divided into at least two zones, the local temperature distribution is measured and they are compared, whereby one zone contains the moulding and the other zone does not.

5. Method according to one or more of

claims 1

to

4

, in which the temperature distribution of several packages is measured simultaneously.

6. Method according to one or more of

claims 3

to

5

, in which an infrared line camera with a resolution of 0.5 to 0.1 K is used.

7. Method according to

claim 6

, in which an infrared line camera with a resolution of 0.2 K is used.

8. Method according to one of

claims 2

to

7

, in which a sensor is used to detect when a package enters and/or leaves the measuring area of the infrared line camera.

9. Method according to one or more of

claims 1

to

8

, in which ventilators are used over the package to increase air exchange over the package prior to the IR detection.

10. Method according to one or more of

claims 1

to

9

, in which the moulding is a contact lens.

11. Apparatus for detecting mouldings consisting of a biocompatible polymeric material, especially ophthalmic lenses, particularly contact lenses consisting of a biocompatible polymeric material, in a blister package, whereby the package is open, characterised by an infrared line camera for recording the temperature, a sensor for detecting when a blister package enters and/or leaves the measuring area of the IR line camera, and an electronic evaluation means, whereby the package is divided into at least two zones, the local temperature distribution is measured and they are compared, and whereby one zone contains the moulding and the other zone does not.

12. Apparatus according to

claim 11

, in which the IR line camera has a resolution of 0.5 to 0.1 K.

13. Apparatus according to

claim 12

, in which the IR line camera has a resolution of 0.2 K.