The 10BPF10-320 Bandpass Filter is a 1 inch (25.4 mm) diameter bandpass filter with a center wavelength of 320 ± 2 nm and a Full Width Half Max of 12 ± 2 nm. See Curve 5, for transmission graph. Our Bandpass Filters pass a narrow spectral band of UV, visible, or NIR radiation and reject out-of-band wavelengths from the X-ray to the far IR. Applications include spectral radiometry, medical diagnostics, chemical analysis, colorimetry, astronomy, and wherever spectral isolation is required.