485nm 대역 통과 필터

Context: This patent describes a quality control method for polyester (PET) films used in optical applications. It relies on measuring the "fluorescence intensity" of the film to ensure it meets low-background-noise requirements.

Usage of Filter: Excitation Filter.

Function: The filter isolates a specific band of blue light (centered at 485nm) from the light source to irradiate the polyester sample.

Result: This allows the system to detect trace amounts of fluorescent impurities or degradation products in the polyester. By using a precise 485nm excitation, the method accurately quantifies the film's intrinsic fluorescence ensuring it is low enough (e.g., fluorescence value <=500) for use in high-precision optical devices.

Context: This patent outlines a highly sensitive method for detecting bromate ions (a potential carcinogen) in water by reacting them with a specific fluorescence derivatizing agent.

Usage of Filter: Emission Filter (Secondary Filter).

Function: While the sample is excited with UV light (around 300-320nm), the 485nm bandpass filter is placed in front of the detector to pass only the specific blue-green fluorescence emitted by the reaction product.

Result: It effectively blocks the UV excitation light and other background signals, allowing for the precise measurement of bromate concentrations at trace levels (micrograms per liter), which is critical for monitoring drinking water safety.

Context: This patent improves retinal imaging by capturing "autofluorescence"—the natural light emitted by retinal tissues (lipofuscin)—to diagnose eye diseases without injecting dyes.

Usage of Filter: Excitation Filter.

Function: The filter restricts the flash or illumination source to a narrow band centered at 485nm.

Result: This specific wavelength optimally excites the lipofuscin in the retina while avoiding the "bleaching" of visual pigments that occurs at other wavelengths. It enables the camera to capture clear, high-contrast images of retinal health markers (like drusen or atrophy) non-invasively.