Handbook of Machine and Computer Vision, 2nd Edition

Chapter 3Lighting in Machine Vision

Irmgard Jahr

Vision & Control GmbH, Mittelbergstraße 16, D-98527 Suhl, Germany

3.1 Introduction

3.1.1 Prologue

One simple part and a hand full of lighting techniques (e.g., Figures 3.1 and 3.2). And everyone looks different. However, there still remain many questions, some of which are

• What do you prefer to see?
• What shall the vision system see?
• What do you need to see? What does the vision system need to see?
• How do you emphasize this? How does the vision system emphasize this?
• Where are the limits?
• Does it work stable in practice?
• What are the components used?
• What light sources are in use?
• What are their advantages and disadvantages?

Figure 3.1 Different lighting techniques applied on a glass plate with a chamfer: (a) diffuse incident bright field lighting, (b) telecentric incident bright field lighting, (c) directed incident dark field lighting, (d) diffuse transmitted bright field lighting, (e) telecentric transmitted bright field, lighting, (f) directed transmitted dark field lighting.

Figure 3.2 Glass plate with a chamfer in the familiar view of the human eye.

Questions over questions. But on the first view everything seemed to be very simple: it is all only made by light, basically caused by the presence of light. But many ...