Optical apparatus for use in image recognition

• US 5,293,428 A
• Filed: 04/28/1992
• Issued: 03/08/1994
• Est. Priority Date: 05/08/1991
• Status: Expired due to Term

• Current Assignee: ROHM Co., Ltd.
• Original Assignee: ROHM Co., Ltd.
• Inventors: Kondou, Yasukazu, Hikita, Hiroaki
• Primary Examiner(s): Mancuso, Joseph
• Application Number:
  US07/874,801
• Time in Patent Office: 679 Days
• Field of Search: 382/8, 382/65, 359/831, 359/834, 359/836, 359/638, 356/390, 356/391, 356/394, 356/373
• US Class Current: 382/146
• CPC Class Codes: G01R 31/308 using non-ionising electromagnetic radiation, e.g. optical radiation investigating or analysing materials by the use of optical means G01N21/00; image analysis G06T7/00
• CPC Class Codes: G06T 2207/30148 Semiconductor; IC; Wafer
• CPC Class Codes: G06T 7/0004 Industrial image inspection

Abstract

An image recognition apparatus comprises a support for placing thereon an inspection object, an impage pickup unit spaced from the support for detecting an image of the inspection object, and an image alternating unit arranged in an optical path extending between the support and the image pickup unit. The image alternating unit includes a quadratic prism which has a longitudinal axis substantially in parallel to the support, and the quadratic prism has two incident surfaces directed toward the support and two exit surfaces directed away from the support.

Claims

1. An image recognition apparatus comprising:

a support for holding an inspection object, the object having a reference line,

an image pickup unit, spaced from the support, for detecting an image of the inspection object,

means for analyzing said image to derive information about the object, the analyzing means being connected to the image pickup unit, and

means for alternating different image portions of the object, the alternating means being arranged in an optical path between the support and the image pickup unit, the alternating means including a quadratic prism having a longitudinal axis substantially parallel to the support and aligned with and parallel to the reference line, the quadratic prism having two incident surfaces directed toward the support for allowing separate entry of two different image portions of the inspection object, the two different image portions originating from opposite sides of the reference line, the quadratic prism further having two exit surfaces directed away from the support for allowing exit of the two different image portions which have been positionally alternated with each other within the quadratic prism,

the quadratic prism comprising means for alternating both of said image portions with respect to the reference line, wherein the image pickup unit comprises means for detecting a composite image which comprises said two image portions which have been positionally alternated with respect to the reference line.

2. The apparatus according to claim 1, further comprising a positioner for moving the support in a plane containing it.

3. The apparatus according to claim 1, further comprising a second quadratic prism arranged between the first-mentioned prism and the image pickup unit, the second prism having a longitudinal axis parallel to the support but perpendicular to the longitudinal axis of the first-mentioned prism, the second prism having two incident surfaces directed toward the support and two exit surfaces directed away from the support, the inspection object being located offset toward one end of the first-mentioned prism, the image pickup unit being located offset toward the other end of the first-mentioned prism.

4. The apparatus according to claim 3, wherein the respective prisms are fixedly held in a support tube.

5. The apparatus according to claim 1, wherein the analyzing means comprises a central processing unit connected to the image pickup unit for processing the detected image of the inspection object.

6. The apparatus according to claim 5, further comprising a manipulator connected to the central processing unit for acting on the inspection object.

7. The apparatus according to claim 1, wherein the image pickup unit has a magnifying object lens.

8. In an image recognition apparatus having a support for holding an inspection object, the object having a reference line, an image pickup unit spaced from the support for detecting an image of the inspection object, and means for analyzing said image to derive information about the object, the analyzing means being connected to the image pickup unit,

the improvement comprising a quadratic prism arranged in an optical path extending between the support and the image pickup unit, the quadratic prism having a longitudinal axis substantially parallel to the support and aligned with and parallel to the reference line, the quadratic prism having two incident surfaces directed toward the support for allowing separate entry of two different image portions of the inspection object, the two different image portions originating from opposite sides of the reference line, the quadratic prism further having two exit surfaces directed away from the support for allowing exit of the two different image portions which have been positionally alternated with each other within the quadratic prism,

the quadratic prism comprising means for alternating both of said image portions with respect to the reference line, wherein the image pickup unit comprises means for detecting a composite image which comprises said two image portions which have been positionally alternated with respect to the reference line.

9. The improvement according to claim 8, further comprising a positioner for moving the support in a plane containing it.

10. The improvement according to claim 8, further comprising a second quadratic prism arranged between the first-mentioned prism and the image pickup unit, the second prism having a longitudinal axis parallel to the support but perpendicular to the longitudinal axis of the first-mentioned prism, the second prism having two incident surfaces directed toward the support and two exit surfaces directed away from the support, the inspection object being located offset toward one end of the first-mentioned prism, the image pickup unit being located offset toward the other end of the first-mentioned prism.

11. The improvement according to claim 10, wherein the respective prisms are fixedly held in a support plane.

12. The improvement according to claim 8, wherein the analyzing means comprises a central processing unit connected to the image pickup unit for processing the detected image of the inspection object.

13. The improvement according to claim 12, further comprising a manipulator connected to the central processing unit for acting on the inspection object.

14. The improvement according to claim 8, wherein the image pickup unit has a magnifying object lens.