BH-A53 Hot Mirror & UV-IR Cut Filter
Narrow the visible passband to warm tones while delivering extended IR rejection across the full thermal spectrum.
- Passband (visible): 437–682 nm, 85.3–91.6 % T
- Cut-off (T50): ≈ 693 nm
- Edge steepness: ~33 nm (90 → 10 % transition)
- IR rejection: < 0.5 % T from 709–1488 nm (OD ≥ 1.3)
- AOI: 0° (normal incidence); custom angles available
- Construction: Ion-assisted hard-oxide; 5–450 mm shapes, 0.21–3.8 mm thick
- Custom options: Edge tuning, extended IR blocking range, 45° AOI for beam-steering, rapid prototypes
Learn more
BH-A53 Hybrid delivers Passband (visible) 437–682 nm, 85.3–91.6 % T, Cut-off (T50) ≈ 693 nm, and Edge steepness ~33 nm (90 → 10 % transition).
The hard-oxide coating is built for repeated handling, heat, and cleaning.
Best suited for:
Warm-tone color imaging, sunset and landscape photography, infrared thermal suppression across extended bands, scientific instruments with color selectivity, cooled detector thermal management systems.
Description
The BH-A53 is a compact hot mirror spanning 423 nm to 693 nm (50 % crossover points) with peak transmission of 91.6 % at 624 nm. It is marginally similar to BH-A51 but with a key distinction: blue transmission is higher at 62.6 % (versus BH-A51's 55.6 %), providing better blue content while still suppressing excessive blue noise. Green (89.1 %), yellow (90.7 %), and red (84.5 %) are comparable to BH-A51, making BH-A53 suitable for applications requiring somewhat broader visible spectrum than BH-A51 without sacrificing the red-dominant character. NIR(700-850) is 2.2 % and NIR(850-1000) is 1.9 %, both very deep, making BH-A53 a thermal-rejection-optimized filter.
Key Advantages
- Balanced blue-red visible spectrum - Blue transmission (62.6 %) is higher than BH-A51, providing better blue content while still controlled and noise-reduced compared to standard HM filters. Enables more balanced visible illumination.
- Compact visible pass-band - The 423-693 nm range (only 270 nm span) is tightly controlled, ideal for applications requiring spectral selectivity and color-specific imaging without broad-spectrum contamination.
- Hard-oxide ion-assisted coating - Advanced durable coating maintains optical performance through thermal cycling, high-intensity light exposure, and long-term operational stress without transmission loss.
- Exceptional NIR suppression - NIR(700-850) at 2.2 % and above 850 nm at 1.9 % represent the deepest IR blocking in the BH-A series, ideal for thermal-sensitive optics and precision measurement.
- Complete custom options - Round, square, free-form blanks from 5 mm to 450 mm diameter, thickness 0.21-3.8 mm, on Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
Typical Applications
- Medical imaging with spectral control - The balanced blue-red spectrum with controlled totality suits tissue-selective imaging modalities where both visible color balance and thermal rejection matter.
- Dental and oral imaging - Enhanced blue response (compared to BH-A51) enables better visualization of light-blue enamel microstructure while maintaining red tissue penetration and thermal management.
- Precision color imaging - The narrow 423-693 nm pass-band with balanced blue-red content supports applications requiring precise color separation and spectral selectivity in quality assurance.
- Fluorescence and multi-color microscopy - Improved blue transmission enables multi-color fluorescence imaging while the compact visible range reduces cross-channel bleed and thermal background noise.
- Industrial vision with thermal stability - The exceptionally deep NIR blocking (2.2 % and 1.9 %) combined with controlled visible spectrum supports high-precision machine vision in thermally challenging industrial environments.
KUPO Optics manufactures BH-A53 in custom specifications-diameter, shape, thickness, and substrate of your choice-with rapid prototype delivery and full production scaling.
FAQ
BH-A53 FAQ
What is BH-A53 and what is it used for?
BH-A53 is a Compact Hot Mirror with Enhanced Blue Response. The BH-A53 is a compact hot mirror spanning 423 nm to 693 nm (50 % crossover points) with peak transmission of 91.6 % at 624 nm. It is marginally similar to BH-A51 but with a key distinction: blue transmission is higher at 62.6 % (versus BH-A51's 55.6 %), providing better blue content while still suppressing excessive blue noise. Common uses include Medical imaging with spectral control, Dental and oral imaging, Precision color imaging, and Fluorescence and multi-color microscopy.
What are the key optical specs of BH-A53?
Key published specs for BH-A53 include Passband (visible): 437–682 nm, 85.3–91.6 % T; Cut-off (T50): ≈ 693 nm; Edge steepness: ~33 nm (90 → 10 % transition); IR rejection: < 0.5 % T from 709–1488 nm (OD ≥ 1.3); AOI: 0° (normal incidence); custom angles available.
What applications is BH-A53 best suited for?
BH-A53 is commonly used for Medical imaging with spectral control, Dental and oral imaging, Precision color imaging, and Fluorescence and multi-color microscopy. Medical imaging with spectral control - The balanced blue-red spectrum with controlled totality suits tissue-selective imaging modalities where both visible color balance and thermal rejection matter.
Can BH-A53 be customized for size, substrate, or coating requirements?
KUPO lists the construction for BH-A53 as Ion-assisted hard-oxide; 5–450 mm shapes, 0.21–3.8 mm thick. Published custom options include Edge tuning, extended IR blocking range, 45° AOI for beam-steering, rapid prototypes. Complete custom options - Round, square, free-form blanks from 5 mm to 450 mm diameter, thickness 0.21-3.8 mm, on Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
What should I know about angle of incidence and durability for BH-A53?
The published angle of incidence for BH-A53 is 0° (normal incidence); custom angles available. The hard-oxide coating is built for repeated handling, heat, and cleaning.
