기능

• Single crystals of germanium used in semiconductors have an infrared wavelength of 2~20 μm and low absorption, so they can be used as optical elements for infrared light.
• It is a single lens made of this germanium crystal.
• Used as a lens for cameras that observe infrared radiation, such as thermography.
• It looks metallic and does not transmit light, but it transmits in the wide infrared range of 2~20 μm.
• Wavelengths below 1.5 μm are not transmitted, so the effect of an infrared transmission filter is also obtained.
• Since the refractive index is more than 4, the curvature is gentler than that of a glass lens.
• Germanium is completely harmless to the human body, so it is safe to use.
• * The germanium lens has a metallic luster, and visible light is not reflected or absorbed and transmitted.
• * The transmittance of a germanium lens without an antireflection coating is about 42% due to surface reflection loss.
• * For infrared wavelength observation, it is necessary to consider the effect of radiation spectrum due to temperature.
• * When using in an environment above 30°C, infrared radiation (around 9.6 μm) is emitted from all materials, and the infrared spectrum of the object to be observed cannot be correctly observed.