Illuminating arrangement for illuminating an object with incident light

• US 5,038,258 A
• Filed: 02/26/1990
• Issued: 08/06/1991
• Est. Priority Date: 03/02/1989
• Status: Expired due to Term

• Current Assignee: Carl Zeiss Industrielle Messtechnik GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: Carl-Zeiss-Stiftung
• Inventors: Koch, Klaus-Peter, Prinz, Reinhard
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): Cole, Richard R.
• Application Number:
  US07/484,890
• Time in Patent Office: 526 Days
• Field of Search: 362/227, 362/249, 362/252, 362/382, 362/11, 362/237, 362/240, 350/527, 350/523, 350/528, 382/8, 356/237
• US Class Current: 362/237
• CPC Class Codes: G01B 11/00 Measuring arrangements characterised by the use of optical techniques
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G02B 21/082 for incident illumination only
• CPC Class Codes: G02B 25/02 with means for illuminating object viewed

Abstract

The invention relates to an illuminating arrangement for illuminating an object with incident light wherein the angle of the incident light is selectable. The illuminating arrangement includes a plurality of individual light sources which can be switched on and off. The light sources are advantageously arranged in several concentric circles in different planes from which the light can be radiated along different beam axes. An illumination at different selectable angles is possible without a mechanical adjustment of the light sources or the imaging elements. The light sources can be advantageously mounted in a hemispherically-shaped carrier. The illuminating arrangement can be a component of a closed control loop and be controlled quickly and completely automatically via an image processing unit or by manual instructions of desired values via a control console.

Claims

1. An illuminating arrangement for illuminating an object with incident light, the illuminating arrangement being for a viewing and imaging device defining an optical axis and the object defining an object plane, the illuminating arrangement comprising:

a plurality of individual light sources defining respective beam axes;

a mounting structure for mounting said light sources in a geometric array defining a geometric array center coincident with said optical axis and for holding said light sources so as to cause said beam axes to intersect said optical axis in said object plane;

control means for controlling the light of said light sources individually and in combination as to their respective intensities for a specific object;

a plurality of spatial light modulators corresponding to respective ones of said light sources; and

,

said control means being connected to said spatial light modulators for electronically driving said light modulators.

2. The illuminating arrangement of claim 1, said geometric array being at least two-dimensional.

3. The illuminating arrangement of claim 1, said plurality of light modulates being a first plurality of light modulators, the arrangement further comprising a second plurality of spatial light modulators distributed in said array so as to be symmetrical with respect to said optical axis of said viewing and imaging device;

and, each one of said second plurality of spatial light modulators being a light structure projector.

4. The illuminating arrangement of claim 3, each of said light structure projectors including means for imaging a light structure on the object which is selectable so as to be specific to the object.

5. The illuminating arrangement of claim 3, said control means including a knowledge-based image processing unit connected to said light sources and said light modulators in a closed control loop for controlling said light sources and said light modulators so as to eliminate surface characteristics of the object which falsify measurement results.

6. The illuminating arrangement of claim 3, said light sources and said light structure projectors being arranged in a single plane perpendicular to said optical axis and being disposed in said plane relative to each other so as to permit an adaptation to different image processing algorithms.

7. The illuminating arrangement of claim 3, said device being part of a measuring apparatus having a z-actuator and said device including an automatic focusing arrangement incorporating at least two of said light structure projectors for generating guide variables for said z-actuator.

8. The illuminating arrangement of claim 1, said individual light sources being respective miniature halogen lamps.

9. The illuminating arrangement of claim 1, said mounting structure being a hemispherically-shaped carrier defining an inner side facing toward said object plane;

and, said individual light sources being fixedly mounted on said inner side.

10. The illuminating arrangement of claim 9, said inner side having a curvature defining a radius having a center located in or near said object plane.

11. The illuminating arrangement of claim 1, further comprising an operating console which includes said control means for controlling the light of said light sources.

12. The illuminating arrangement of claim 1, said control means including a knowledge-based image processing unit connected to said light sources in a closed control loop for controlling the respective intensities thereof;

and, said image processing unit including means for eliminating surface characteristics of the object which falsify measurement results.

13. The illuminating arrangement of claim 1, said plurality of light modulators being a first plurality of light modulators, the arrangement further comprising a second plurality of spatial light modulators distributed in said array so as to be symmetrical with respect to said optical axis of said viewing and imaging device;

and, each one of said second plurality of spatial light modulators being a light structure projector.

14. The illuminating arrangement of claim 13, said control means including a knowledge-based image processing unit connected to said light sources in a closed control loop for controlling the respective intensities thereof;

and, said image processing unit including means for eliminating surface characteristics of the object which falsify measurement results.

15. The illuminating arrangement of claim 1, said control means including a knowledge-based image processing unit connected to said light sources and said light modulators in a closed control loop for controlling said light sources and said light modulators so as to eliminate surface characteristics of the object which falsify measurement results.