Method, apparatus and computer program product for sensing of visible spectrum and near infrared spectrum

An apparatus comprising:

• an image capture module comprising:
• a lens configured to receive incident light;
• an IR cut-off filter configured to receive the incident light from the lens and filter the incident light to generate filtered light, the IR cut-off filter comprising a plurality of pixels with pass-band characteristics for visible light wavelengths associated with the incident light, the plurality of pixels configured to perform stop-band attenuation of near infrared (NIR) wavelengths associated with the incident light for filtering of the incident light, the stop-band attenuation of the NIR wavelengths configured to vary based on spatial location of pixels of the plurality of pixels within the IR cut-off filter;
• and
• an image sensor configured to sense the filtered light received from the IR cut-off filter to generate sensed light, wherein the IR cut-off filter comprises spatially varying transparency attributes configured to vary along a direction to configure a cosine-function of spatial location based attenuation;
• at least one processor;
• and
• at least one memory comprising computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to at least perform:
• determine a baseband signal with an unmodulated visible spectrum and an amplitude modulated NIR signal by performing the cosine-function based transformation of the sensed light;
• determine a NIR spectrum associated with the incident light by demodulating the modulated NIR signal;
• and
• determine a visible spectrum associated with the incident light based on the NIR spectrum and the baseband signal.

A computer program product comprising at least one non-transitory computer-readable storage medium, the non-transitory computer-readable storage medium comprising a set of instructions, which, when executed by one or more processors, cause an apparatus to at least perform:

• filter incident light by an IR cut-off filter disposed in an optical path between a lens and an image sensor to generate filtered light, the IR cut-off filter comprising a plurality of pixels with pass-band characteristics for visible light wavelengths associated with the incident light, the plurality of pixels configured to perform stop-band attenuation of near infrared (NIR) wavelengths associated with the incident light for filtering of the incident light, the stop-band attenuation of the NIR wavelengths configured to vary based on spatial location of pixels of the plurality of pixels within the IR cut-off filter;
• sense the filtered light received from the IR cut-off filter by the image sensor to generate sensed light, wherein the IR cut-off filter comprises spatially varying transparency attributes configured to vary along a direction to configure a cosine-function of spatial location based attenuation;
• determine a baseband signal with an unmodulated visible spectrum and an amplitude modulated NIR signal by performing the cosine-function based transformation of the sensed light;
• determine a NIR spectrum associated with the incident light by demodulating the modulated NIR signal;
• and
• determine a visible spectrum associated with the incident light based on the NIR spectrum and the baseband signal.

An apparatus comprising:

• an image capture module comprising:
• a lens configured to receive incident light;
• an IR cut-off filter configured to receive the incident light from the lens and filter the incident light to generate filtered light, the IR cut-off filter comprising a plurality of pixels with pass-band characteristics for visible light wavelengths associated with the incident light, the plurality of pixels configured to perform stop-band attenuation of near infrared (NIR) wavelengths associated with the incident light for filtering of the incident light, the stop-band attenuation of the NIR wavelengths configured to vary based on spatial location of pixels of the plurality of pixels within the IR cut-off filter;
• and
• an image sensor configured to sense the filtered light received from the IR cut-off filter to generate sensed light, wherein the IR cut-off filter comprises spatially varying transparency attributes configured to vary along a direction to configure a cosine-function of spatial location based attenuation;
• means for determining a baseband with an unmodulated visible spectrum signal and an amplitude modulated NIR signal by performing the cosine-function based transformation of the sensed light;
• means for determining a NIR spectrum associated with the incident light by demodulating the modulated NIR signal;
• and
• means for determining a visible spectrum associated with the incident light based on the NIR spectrum and the baseband signal.