Optical measurement system for detecting luminescence or fluorescence signals

• US 6,191,852 B1
• Filed: 10/13/1998
• Issued: 02/20/2001
• Est. Priority Date: 10/14/1997
• Status: Expired due to Term

• Current Assignee: Bayer Intellectual Property GmbH (Bayer AG)
• Original Assignee: Bayer AG
• Inventors: Bechem, Martin, Paffhausen, Wolfgang
• Primary Examiner(s): Font, Frank G.
• Assistant Examiner(s): Ratliff, Reginald A.
• Application Number:
  US09/170,482
• Time in Patent Office: 861 Days
• Field of Search: 356/311, 356/422, 356/244, 356/418, 356/419
• US Class Current: 356/244
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 21/6452 Individual samples arranged in a regular 2D-array, e.g. multiwell plates
• CPC Class Codes: G01N 21/763 Bioluminescence
• CPC Class Codes: G01N 35/028 having reaction cells in the form of microtitration plates

Abstract

In the measurement system for detecting optical signals of microassays, the signal-generating test objects 5 are arranged on an investigation surface of a planar carrier 4. The planar carrier 4 is, in particular, a microtitre plate for biological objects. In principle, the measurement system comprises an optical imaging arrangement which reduces the size of the test objects 4 to be measured in such a way that all the objects are imaged completely on a two-dimensional, photosensitive image sensor 6. For imaging, a high-resolution glass-fiber taper element 1 having a large-area 2 and a small-area end 3 is used in this case, whose end surfaces 2, 3 are selected such that the large-area end surface 2 corresponds at least to the investigation surface of the carrier 4 and the small-area end surface 3 corresponds to the size of the image sensor 6, the ratio of the end surfaces 2, 3 producing the scale of reduction of the optical imaging arrangement in order to image the investigation surface of the carrier 4 completely onto the image sensor 6.

Claims

1. Measurement system for detecting optical signals of microassays, in which the signal-generating test objects (5) are arranged on an investigation surface of a planar carrier (4), comprising an optical imaging arrangement which reduces the size of the test objects (5) to be measured in such a way that all the objects are imaged completely on a two-dimensional, photosensitive image sensor (6), characterized in that the optical imaging arrangement comprises a high-resolution glass-fibre taper element (1) having a large-area (2) and a small-area end (3) and the end surfaces (2, 3) are chosen such that the large-area end surface (2) corresponds at least to the investigation surface of the carrier (4) and the small-area end surface (3) corresponds to the size of the image sensor (6), the ratio of the end surfaces (2, 3) producing the scale of reduction of the optical imaging arrangement in order to image the investigation surface of the carrier (4) completely onto the image sensor (6) wherein the planar carrier comprises a plate (4) having a multiplicity of holes (9) for receiving the signal-generating test objects (5), in that the image sensor (6) comprises an image intensifier (10) and a video camera (11) for converting the intensified image signals into electronic signals, and in that the glass-fibre taper element (1) generates a reduced image of the plate (4) that fully fills the entry window (15) of the image intensifier (10).

2. Measurement system according to claim 1, wherein the image intensifier (10) has a bialkali photocathode whose spectral sensitivity at wavelengths>

700 nm is<

1%.

3. Measurement system according to claim 1, wherein the plate (4) is arranged in a horizontally movable and vertically adjustable, drawer-like mount (24), which, after horizontal retraction, is raised to an extent such that the large-area end (2) of the glass-fibre taper element (1) is in direct contact with the surface of the plate (4).

4. Measurement system according to claim 1, wherein the small-area end (3) of the glass-fibre taper element (1) is in direct optical contact with the entry window (15) of the image intensifier (10).

5. Measurement system according to claim 1, wherein the entry window (15) of the image intensifier (10) is formed by a glass-fibre plate which transfer the image directly onto the photocathode (16) of the image intensifier (10) situated behind it.

6. Measurement system according to claim 1, wherein in order to minimize reflection losses, an air gap (17) remaining between the glass-fibre taper element (1) and the entry window (15) of the image intensifier (10) is filled with an oil film (20), whose refractive index corresponds to the refractive index of the taper element (1).

7. Measurement system according to claim 1, wherein the plate (4) has an optically transparent base (23), in that the drawer-like mount (24) is designed as a frame construction (25) and in that a light source for fluorescence excitation which generates a light pencil (33) of inclined incidence with respect to the optical axis is arranged underneath the plate (4).

8. Measurement system according to claim 1, wherein the entire apparatus can be pivoted through 180°

about a horizontal spindle (12) and has the following further features;

a) the plate (4) has an optically transparent base (23),

b) the drawer-like mount (24) for the plate (4) is designed as a frame construction (25),

c) the measurement system additionally has a pipetting system (35) whose individual pipettes (36) are assigned to the test holes (9) in the plate (4).

9. Measurement system according to claim 1, wherein said plate (4) is a microtitre plate.