What is chromatic aberration in endoscope cameras?

Introduction
Ever seen purple or green fringes around bright edges in an endoscope image? That’s chromatic aberration. It is an optical flaw that reduces sharpness and colour accuracy. In medical diagnosis or industrial inspection, it can hide subtle tissue changes or make cracks harder to see. Understanding what causes it helps you choose a better endoscope camera module. At Sincere, we have manufactured cmos module camera solutions for over 30 years, including industrial endoscope camera module designs with corrected optics. This article explains chromatic aberration, why it matters, and what to look for.

What Is Chromatic Aberration?
Chromatic aberration (colour fringing) happens because a lens bends different colours of light by different amounts. Blue light bends more than red light. When white light passes through a lens, colours do not focus at the same point – creating coloured halos around high‑contrast edges.

Two main types:

• Axial (longitudinal): Different colours focus at different distances. Causes coloured blur over the whole image.

• Lateral (transverse): Different colours are magnified differently. Causes fringing that increases toward the edges.

In an endoscope camera module, lateral aberration is more common because endoscope lenses are often wide‑angle.

Why It Matters

For an hd endoscope camera used in medicine, colour accuracy is critical. A purple fringe on a polyp could be mistaken for a different tissue. In an industrial endoscope camera module, a false colour fringe might hide a crack’s true edge, leading to wrong measurements.

How Resolution Affects Visibility
Higher resolution sensors make chromatic aberration more visible. A 1080p endoscope camera module with poor optics will show obvious fringing. A VGA camera might mask it. As endoscopes move to 4K, good colour correction becomes essential.

What Causes It in Endoscopes?
Endoscope lens assemblies are tiny – often 2–5mm diameter. Making a small, wide‑angle lens that focuses all colours perfectly is hard. Manufacturers use:

• Multiple lens elements (achromatic or apochromatic designs)

• Aspherical elements

• Low‑dispersion glass

Low‑cost camera module designs may use one or two plastic lenses – they suffer strong chromatic aberration. Quality industrial endoscope camera module designs use multiple glass elements.

How to Spot Chromatic Aberration
Look at a high‑contrast edge – a black line on white, or a bright LED against dark background. If you see a purple or green halo on one side, that is lateral aberration. If the whole image has coloured edges everywhere, that is axial aberration.

Minimising Chromatic Aberration

• Choose a good lens: A cmos module camera with a multi‑element glass lens has much less fringing.

• Use the image centre: Lateral aberration worsens toward edges.

• Software correction: Some processors can reduce visible fringing (but does not restore lost detail).

• Buy from a reputable manufacturer: Sincere uses properly corrected achromatic lenses.

Examples by Endoscope Type

HD Endoscope Camera – A good hd endoscope camera (720p/1080p) shows minimal fringing. Medical endoscopes often use apochromatic lenses.

Industrial Endoscope Camera Module – For inspecting turbine blades or welds, low chromatic aberration is essential. High‑end industrial modules use glass multi‑element lenses.

1080p Endoscope Camera Module – A quality 1080p endoscope camera module includes an achromatic doublet. Fringing is rarely noticeable. Cheap USB endoscopes have obvious purple fringing.

CMOS Module Camera – The sensor does not cause chromatic aberration – it is a lens property. A high‑resolution sensor reveals lens flaws. At Sincere, we match lens quality to sensor resolution.

Sincere’s Approach
At Sincere, we design endoscope camera module optics to minimise chromatic aberration:

• Multi‑element glass lenses for medical and industrial modules.

• Optimised designs for cost‑sensitive modules – fringing kept acceptable.

• Testing with high‑contrast targets to ensure minimal fringes.

• Custom lenses for specific wavelengths (e.g., narrow‑band imaging).

Summary
Chromatic aberration is colour fringing caused by a lens bending different colours differently. It reduces sharpness and can mislead inspection. For an endoscope camera module, good optics – multi‑element glass lenses – are essential. When choosing an hd endoscope camera, industrial endoscope camera module, or 1080p endoscope camera module, pay attention to lens quality. A cmos module camera with a poor lens disappoints. A well‑corrected camera module delivers sharp, colour‑accurate images you can trust.

Contact Sincere to discuss your endoscope camera module and chromatic aberration requirements.