The 635nm bandpass filter, as a precision optical component, has its core parameters determining the filtering performance within a specific wavelength range. The central wavelength can be controlled at 635±2nm, ensuring precise transmission of the target red light band. In terms of transmittance, the product achieves a transmittance of T>91%, and its high transmittance characteristic effectively reduces the loss of the target light signal. There are slight differences in the half-bandwidth parameter, and the bandwidth selection needs to be comprehensively considered based on the wavelength range of the light source and anti-interference requirements. The blocking bands cover 400nm-610nm and 670nm-1100nm, with a blocking rate requirement of T<0.1%, which can strongly suppress interference from ultraviolet, visible, and infrared stray light.

Material and Process Advantages of the 635nm Bandpass Filter

• Substrate Selection: Imported ultra-thin optical glass is used, featuring high transmittance (>91%), excellent smoothness, small thickness tolerance (±0.1mm), and good flatness, providing a foundation for high-precision optical performance.
• Coating Process: Ion sputtering coating technology is implemented using imported equipment, giving the coating advantages such as high durability (adhesion ≥5N), good spectral uniformity (±2nm), and strong central wavelength stability (temperature drift <0.01nm/°C), enabling it to adapt to complex working environments.

• Typical Application Fields of the 635nm Bandpass Filter

  1. Laser Processing Equipment: Paired with a 10,000W Trumpf TruFlow series CO? laser, it is used for metal cutting, welding, and surface treatment, reducing laser loss by over 30% and lowering the frequency of protective lens replacement.
  2. Photoelectric Measuring Instruments: Suitable for red light LD laser pumping, IR rangefinders, and lidar systems, it can filter out over 85% of stray light, improving ranging accuracy to ±1mm.
  3. Biometric Technology: In fingerprint recognition and iris imaging systems, it can accurately align with the inner edge of the pupil and eliminate interference from eye fluids, optimizing the image signal-to-noise ratio to over 40dB.
  4. Special Light Source Applications: Compatible with 640nm LED lights, red laser semiconductors, and other light sources, it is widely used for spectral control in scenarios such as stage lighting and medical detection.