Apparatus and method for measuring contamination of filter
Provided are an apparatus and method for measuring contamination of a filter. The filter contamination measuring apparatus includes a light-emitting unit which provides light having, a predetermined wavelength to a filter adsorbs foreign materials, a light-receiving unit which receives light reflected by the filter and convert reflected light information into a digital code to output, and a contamination calculating unit which processes the digital code provided by the light-receiving unit and calculates a degree of contamination of the filter, wherein the contamination calculating unit calculates a degree, in which a wavelength of the light reflected by the filter is shifted from the predetermined wavelength, compares intensity of light provided by the light-emitting unit with intensity of the light reflected by the filter, and calculates the degree of contamination of the filter.
1. A filter contamination measuring apparatus, comprising:
a light-emitting unit configured to provide a first light having a predetermined wavelength to a filter configured to adsorb foreign materials;
at least one sensor configured to receive a second light reflected by the filter, convert information of the second light into a digital code, and output the digital code; and
a processor configured to calculate wavelength and intensity of the second light by processing the digital code provided by the at least one sensor and calculate a degree of contamination of the filter,
wherein the processor calculates the degree of contamination of the filter based on a wavelength shifting value which is calculated by comparing the wavelength of the second light with the predetermined wavelength of the first light, and an intensity variation value which is calculated by comparing the intensity of the second light with an intensity of the first, and
wherein the wavelength shifting value includes a difference between the predetermined wavelength of the first light and the wavelength of the second light or a ratio of the wavelength of the second light to the predetermined wavelength of the first light, and the intensity variation value includes a difference between the intensity of the first light and the intensity of the second light or a ratio of the intensity of the second light to the intensity of the first light.
2. The apparatus of claim 1 , further comprising:
a first lens configured to uniformly irradiate the filter with the light provided by the light-emitting unit; and
a second lens configured to collect the light reflected by the filter and irradiate the at least one sensor with the collected light.
3. The apparatus of claim 1 , wherein the at least one sensor comprises:
a color sensor configured to detect light of red, green, and blue wavelengths and output electrical signals corresponding to the detected wavelengths; and
an ambient light sensor (ALS) configured to detect light intensity.
4. The apparatus of claim 3 , wherein the color sensor comprises:
unit sensors configured to detect light of red, green, and blue wavelengths;
an amplifier configured to amplify signals output from the unit sensors; and
an analog-to-digital converter (ADC) configured to convert signals output from the amplifier into digital codes, and
wherein the ambient light sensor comprises:
a luminosity sensor configured to detect intensity of received light;
an amplifier configured to amplify a signal output from the luminosity sensor; and
an ADC configured to convert a signal output from the amplifier into a digital code.
5. The apparatus of claim 1 , wherein the light-emitting unit provides light of a wavelength in a range of 400 nm to 500 nm.
6. The apparatus of claim 1 , wherein the at least one sensor has sensitivity with respect to light of a wavelength in a range of 400 nm to 600 nm higher than those of the other wavelengths.
7. The apparatus of claim 1 , wherein the filter is a high efficiency particulate air (HEPA) filter.