Making surface temperatures or heat flows visible by thermographic systems is a common imaging technique on a large scale – for example, detecting energy losses of buildings. It also works for quality inspection in the microscale. However, this requires outstanding infrared optics that are characterized by highest transmission and best image quality. This is exactly what the DIOPTIC infrared microscope objective with 0.25x magnification does.
Infrared microscopy at the limit
For thermography on smallest structures, DIOPTIC has developed special infrared microscope lenses designed for use with cooled MWIR VGA sensors. The current series includes five lenses with magnification ranges from 0.25x to 10x. Among these “Best of Five,” the 0.25x stands out in particular. Why? Because the experts at DIOPTIC have once again pushed the limits of what is physically feasible.
Advantages of the telecentric design
The 0.25x is a telecentric lens. This means that the chief ray on the object side is parallel to the optical axis. This design has several advantages: On the one hand, the system is able to capture objects without perspective distortion; the image scale is maintained even with axial object displacement. Second, ambient stray light is significantly minimized. This factor is crucial because thermal stray light effects have a negative impact on the measurement.
Unmatched in transmission, contrast and detection
Compared to conventional lenses, the 0.25x with telecentric imaging can visibly demonstrate its advantages (see image examples). Thanks to the highest transmission and a consistently detailed image, the DIOPTIC lens 0.25x sets standards in thermographic microscopy – especially where every micrometer resolution counts. This applies equally to semiconductor manufacturing as well as to other fields of microelectronics, materials processing and industrial metrology. Malte Hagemann, Division Head IR Lenses at DIOPTIC, is convinced: “I’m not aware of anything comparable on the market.”
Depending on the application and requirement profile, we also realize customer-specific lenses and infrared systems at the highest level.
