The right combination of lighting technique, angle and source — engineered to make defects visible and inspections reliable.
Lighting plays a critical role in the performance of a machine vision system, especially for tasks like defect detection, measurement, inspection, counting and tracking. Proper lighting enhances image quality, ensuring accurate processing and reliable results. The right combination of lighting techniques and angles can make the difference between success and failure in defect detection.
Illuminates the object from behind, creating sharp contrast between the object and the background. Ideal for edge detection, measurement and silhouette-based inspections.
Common apps · Gauging, profile inspection, and detection of transparent materials.
Provides even, shadow-free illumination by reflecting light from a dome-shaped surface. Perfect for highlighting subtle surface features without glare.
Common apps · Inspection of shiny or reflective surfaces like metal, glass or plastics.
Positioned around the camera lens, ring lights provide uniform, directional light toward the object — useful for general-purpose lighting and reducing shadows.
Common apps · Inspection, tracking and counting of small objects.
Light is placed at a low angle to highlight surface textures, scratches and defects by casting shadows on surface imperfections.
Common apps · Surface defect detection in glass, plastic and polished metals.
Emits light vertically onto a target from the same axis as the camera and lens. Also known as brightfield or diffuse on-axis lighting.
Common apps · Inspection of flat, reflective surfaces such as wafers and LCD panels.
Projects patterns such as grids or stripes onto an object, enhancing 3D surface inspection and measurement.
Common apps · Height measurement, 3D inspection and volume analysis.
Selecting the ideal lighting requires careful consideration of the object being inspected, the features that need to be detected, and the layout of the system. Ask yourself the following:
Field of view and object size: How big is the area you need to capture, and what are the dimensions of the object?
Distance to camera and lighting: How far is the object from both the camera and the light source?
Type and intensity of light: What lighting method and brightness level will provide the best illumination for accurate inspection?
Feature characteristics: What are the specific attributes of the features you are inspecting, and which lighting technique will best reveal them?
Surface properties and material: What is the texture and material of the object, and how will these affect the way light interacts with it?
Object color: Does the object color call for a particular light color to enhance contrast — white, red, blue, green, or specialized lighting like infrared (IR) or ultraviolet (UV)?
In machine vision, several types of lighting sources are commonly used:
Popular for small- to medium-scale inspection stations due to its efficiency and widespread availability.
Known for its greater intensity, making it suitable for inspections that require strong illumination.
Offers long life expectancy and is highly adaptable — a common choice for many inspection stations.
Frequently used in microscopy due to its discrete wavelength peaks, ideal for fluorescence studies.
A powerful source for applications that require a bright strobe light, often used in large-scale setups.
Each lighting type serves different purposes depending on the scale of the inspection and the specific lighting requirements.
The angle at which light hits the object is crucial in machine vision systems. Improper lighting angles can result in reflection or glare, which can obscure details and lead to inaccurate analysis.
Enhances surface textures and highlights defects by casting long shadows.
Minimizes shadows and reflection but may reduce visibility of fine surface details.
By carefully adjusting the lighting angle, you can avoid unwanted reflections and achieve optimal contrast — ensuring even the smallest defects are detected.
A diffuser is a translucent material used to scatter light, providing soft and even illumination across the object. It helps eliminate shadows and hotspots, which can otherwise interfere with the machine vision system's accuracy.
In machine vision, diffusers are essential when inspecting highly reflective surfaces. Without a diffuser, light reflections can create bright spots or glare, causing the camera to miss important details. A diffuser helps by spreading the light more evenly, reducing the harsh reflections and allowing the system to capture clearer, more uniform images.
Diffusers are particularly useful in:
Share your inspection target, surface, working distance and throughput — our engineers will recommend the optimal lighting technique, source and angle.
©2026 Intelgic Inc. All Rights Reserved.
