Endoscopes are essential diagnostic and treatment devices in minimally invasive surgery. However, when the surgery reaches a critical stage, the images may suddenly become blurry, reddish, or even noisy—these problems are not caused by endoscope malfunction, but by the lens overheating. To control its internal temperature, a thermoelectric cooler (TEC) can be placed inside the endoscope, which is less than 5 millimeters in diameter. This keeps the temperature within a stable operating range, preventing the endoscope from fogging and avoiding surgical errors caused by blurred images.

I.Why do endoscopes fog up easily?

Endoscopes are typically inserted directly into the human body from room temperature. Because the lens surface is relatively cold, moisture quickly condenses into fog upon contact with the warm, humid air inside the body—similar to how glasses fog up when worn indoors in winter. Simultaneously, the LED light source and image sensor inside the endoscope continuously generate heat during operation, leading to a significant decrease in image quality: increased noise, color distortion, and in severe cases, difficulty in distinguishing blood vessels or tissue boundaries.

II.Why choose thermoelectric temperature control solution

Because the part of the endoscope inserted into the human body is very thin, with a diameter of only 4-8mm, fitting an active cooling unit into such a confined space presents significant challenges: First, its size must be small enough not to interfere with the lens, optical fiber, and flushing channel; second, its operation must be silent and vibration-free, as any noise or vibration will affect imaging; furthermore, since endoscopes require sterilization, the cooling element must withstand a high-temperature, high-pressure steam sterilization environment of 134℃.

▲Miniature thermoelectric cooler

Addressing the challenges of confined internal spaces and stringent temperature control requirements in endoscopes, the FerroTec team developed a miniature semiconductor cooling chip specifically for medical endoscopes—less than 4mm in diameter and less than 2mm thick. This cooling chip, with its zero moving parts, quiet operation, and zero vibration, is well-suited for high-precision imaging scenarios; it can also withstand high-temperature, high-pressure steam sterilization at 134℃, meeting medical device sterilization standards. Combined with a miniature temperature sensor, the system can perform real-time closed-loop monitoring of the lens temperature: when the temperature exceeds the normal range, the system automatically activates/intensifies cooling; once the target temperature is reached, the system immediately reduces cooling to prevent condensation on the surface due to overcooling.

III.Advantages of Thermoelectric Cooling Technology in Endoscopes

Real-world testing results show that in high-temperature and high-humidity environments, endoscopes equipped with micro-TEC maintain clear and stable images after two hours of continuous operation; while endoscopes using passive cooling methods exhibit fogging and image distortion within half an hour. This demonstrates that thermoelectric cooling technology not only helps surgeons maintain a high-definition and stable field of vision during surgery, reducing the risk of misjudgment due to blurred or distorted images, but also significantly improves surgical efficiency—surgeons can perform multiple surgeries consecutively without needing to stop the machine to cool down. Simultaneously, effective temperature control of the image sensor extends the lifespan of the equipment, thereby reducing subsequent maintenance costs. Currently, this temperature control solution is widely used in various endoscopic products such as laparoscopes, hysteroscopes, and ENT endoscopes, and has almost become a standard configuration, especially in high-end models such as 4K ultra-high-definition and fluorescence imaging systems.

As a leading global supplier of thermoelectric cooling devices, FerroTec provides high-performance miniature thermoelectric cooling chips for the medical industry, with customizable power, materials, and appearance. For product details or to obtain solutions, please contact us at 0571-89712612.