Sensing apparatus having optical assembly that collimates emitted light for detection

• US 20070205365A1
• Filed: 03/03/2006
• Published: 09/06/2007
• Est. Priority Date: 03/03/2006
• Status: Active Grant

• Current Assignee: 3D Systems, Inc. (3D Systems Corporation)
• Original Assignee: Vidar Systems Corporation (3D Systems Corporation)
• Inventors: Lee, Jason, Smitt-Jeppesen, Sigrid, Lee, Sung, Smitt, Asbjorn
• Granted Patent: US 7,528,374 B2
• Time in Patent Office: Days
• US Class Current: 250/339.120
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0202 Mechanical elements; Supports for optical elements
• CPC Class Codes: G01J 3/0208 using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
• CPC Class Codes: G01J 3/0232 using shutters
• CPC Class Codes: G01N 21/6452 Individual samples arranged in a regular 2D-array, e.g. multiwell plates
• CPC Class Codes: G01N 2201/10 Scanning
• CPC Class Codes: G01N 2201/1047 with rotating optics and moving stage

Abstract

An apparatus for optical sensing of samples includes an optical source, an optical assembly, a sample holder, an objective lens, and a detector. The objective lens collimates light emitted by the sample. Preferably, the optical assembly rotates about an axis, allowing the sensing apparatus to sense results from plural locations on a sample without moving the sample. Moving the sample in a linear direction while rotating the optical assembly allows sensing of an entire sample. Preferably, light from the optical source enters the optical assembly along the axis of rotation. Sensing methods consistent with the invention are also described.

Claims

1. A sensing apparatus comprising:

a sample holder configured to receive a sample;

an optical source configured to emit excitation light;

an optical assembly configured to receive the excitation light, the optical assembly being spaced from the sample holder and being rotatable about an axis;

an objective lens; and

a detector, wherein

the optical assembly is configured to direct the excitation light to a first location on the sample when the optical assembly is in a first position, and to direct the excitation light from the optical source to a second location on the sample when the optical assembly is rotated to a second position,

the objective lens is configured to collimate light emitted from the first and the second locations on the sample, and

the detector is configured to receive the collimated light.

2. The sensing apparatus of claim 1, wherein the optical source comprises a laser.

3. The sensing apparatus of claim 1, wherein the axis is a first axis and the optical assembly directs the excitation light to the sample along a second axis.

4. The sensing apparatus of claim 3, wherein a distance from the first axis to the second axis defines a radius of a circle, the circle comprises an arc, and the sensing apparatus is configurable to direct excitation light to the sample while the optical assembly rotates through the arc.

5. The sensing apparatus of claim 4, wherein the arc is a first arc, the circle comprises a second arc, and the sensing apparatus is configurable to direct excitation light to the sample while the optical assembly rotates through the second arc.

6. The sensing apparatus of claim 5, wherein the sensing apparatus directs excitation light to the sample while the optical assembly rotates through the first and second arcs.

7. The sensing apparatus of claim 5, wherein the optical source is a first optical source, the excitation light is first excitation light, the sensing apparatus further comprising a second optical source outputting second excitation light, wherein the sensing apparatus is configurable to direct second excitation light to the sample.

8. The sensing apparatus of claim 7, wherein the sensing apparatus directs first excitation light to the sample while the optical assembly rotates through the first arc, and the sensing apparatus directs second excitation light to the sample while the optical assembly rotates through the second arc.

9. The sensing apparatus of claim 7, wherein the sensing apparatus directs first and second excitation light to the sample while the optical assembly rotates through the first arc, and the optical source directs first and second excitation light to the sample while the optical assembly rotates through the second arc.

10. The sensing apparatus of claim 7, wherein the sensing apparatus directs first excitation light to the sample while the optical assembly completes a first rotation around the circle, and the sensing apparatus directs second excitation light to the sample while the optical assembly completes a second rotation around the circle.

11. The sensing apparatus of claim 7, further comprising an optical chopper configured to allow one of the first excitation light and the second excitation light to reach the sample at a time.

12. The sensing apparatus of claim 7, further comprising a second detector, wherein the first detector is configured to detect first light emitted by the sample in response to the first excitation light and the second detector is configured to detect second light emitted by the sample in response to the second excitation light.

13. The sensing apparatus of claim 3, wherein the optical assembly comprises a mirror, the mirror being aligned with the second axis, and the mirror reflecting the excitation light.

14. The sensing apparatus of claim 1, wherein the objective lens comprises an aspherical lens.

15. The sensing apparatus of claim 1, wherein the detector is aligned along the axis.

16. The sensing apparatus of claim 1, wherein the sample includes a biochip.

17. The sensing apparatus of claim 1, wherein the sample holder is configured to move.

18. The sensing apparatus of claim 17, wherein the sample holder is configured to move in a linear direction.

19. The sensing apparatus of claim 1, wherein the detector comprises a photomultiplier tube.

20. The sensing apparatus of claim 19, wherein the objective lens collimates the emitted light into a beam that substantially covers a light-sensing surface of the photomultiplier tube.