What is an athermalized lens in thermal cameras?

Table of Contents

1. Introduction
2. What is an Athermalized Lens?
3. Importance in Thermal Cameras
4. Technical Aspects of Athermalized Lenses
5. Savgood Company Solutions
6. References

Introduction

The use of athermalized lenses in thermal cameras is pivotal for ensuring accurate thermal imaging under varying ambient temperature conditions. This article delves into the nature of athermalized lenses, their significance, technical specifications, and solutions provided by companies such as Savgood.

What is an Athermalized Lens?

An athermalized lens is designed to maintain focus consistency in a thermal camera irrespective of temperature fluctuations, typically between -40°C and +85°C. It achieves this through a combination of materials and design that counteract the effects of thermal expansion and refractive index changes.

Importance in Thermal Cameras

Maintaining image focus in thermal cameras is crucial for accurate temperature measurement and effective image processing. Athermalized lenses enhance the reliability of thermal cameras by preventing defocus that can occur due to temperature-induced changes in lens dimensions and materials.

Technical Aspects of Athermalized Lenses

Athermalized lenses are constructed using materials with minimal thermal expansion coefficients. For instance, germanium and chalcogenide glasses are often used due to their stable properties over wide temperature ranges.

Design techniques such as using a combination of positive and negative lens elements help in achieving thermal compensation. A typical specification of an athermalized lens might include:

• Focal Length: 50 mm
• Aperture: f/1.0
• Wavelength: 8-14 µm (Long-Wave Infrared)
• Operating Temperature Range: -40°C to +85°C
• Material: Germanium/Chalcogenide

Savgood Company Solutions

Savgood provides advanced thermal imaging solutions featuring athermalized lenses. Their products emphasize robustness in extreme environments and precision in thermal detection. Notable offerings include:

• SG-TM50: Incorporates a 50 mm athermalized lens, designed for use in surveillance and industrial monitoring.
• SG-TM100: Utilizes a 100 mm athermalized lens for long-range thermal detection.

References

1. Smith, W. J. Modern Optical Engineering: The Design of Optical Systems. McGraw-Hill, 2008.
2. Goodman, J. W. Introduction to Fourier Optics. Roberts and Company Publishers, 2005.
3. Savgood, Thermal Imaging Solutions, Savgood Official Website, 2023.