Image sensor including color and infrared pixels

An image sensing system, comprising:

• an IR notch filter configured to block transmission of spectral energy having wavelengths in an interface region between the visible spectrum and the invisible spectrum and enable transmission of spectral energy having wavelengths in at least the visible spectrum and the near-infrared (IR) spectrum;
• a digital image sensor comprising a two-dimensional array of pixel elements, the digital image sensor configured to generate output signals at each pixel element as pixel data representing an image of a scene;
• and
• a color filter array comprising a two-dimensional array of selectively transmissive filters superimposed on and in registration with the two-dimensional array of pixel elements, the color filter array comprising a first group of selectively transmissive filters disposed to transmit spectral energy in one or more colors of the visible spectrum and a second group of gray color filters disposed to transmit spectral energy in at least the near-infrared (IR) spectrum,
• wherein the gray color filter is formed using a linear combination of the red, green and blue color filters, and
• wherein the gray color filter transmits spectral energy in the red, green and blue colors of the visible spectrum at 30% intensity and transmits spectral energy of the infrared spectrum at wavelengths above about 780 nm.

A method for sensing an image of a scene comprising:

• receiving incident light at a digital image sensing system;
• blocking transmission of spectral energy having wavelengths in an interface region between the visible spectrum and the invisible spectrum while enabling transmission of spectral energy having wavelengths in at least the visible spectrum and the near-infrared (IR) spectrum;
• blocking transmission of spectral energy having wavelengths between approximately 650 nm and approximately 780 nm;
• sensing the incident light at a digital image sensor overlaid with a color filter array, comprising:
• sensing the incident light using a first group of selectively transmissive filters disposed to transmit spectral energy in one or more colors of the visible spectrum;
• and
• sensing the incident light using a second group of gray color filters disposed to transmit spectral energy in at least the near-infrared (IR) spectrum;
• and
• generating output signals at each pixel element of the digital image sensor as pixel data representing an image of a scene.

A method for sensing an image of a scene comprising:

• receiving incident light at a digital image sensing system;
• blocking transmission of spectral energy having wavelengths in an interface region between the visible spectrum and the invisible spectrum while enabling transmission of spectral energy having wavelengths in at least the visible spectrum and the near-infrared (IR) spectrum;
• sensing the incident light at a digital image sensor overlaid with a color filter array, comprising:
• sensing the incident light using a first group of selectively transmissive filters disposed to transmit spectral energy in one or more colors of the visible spectrum;
• and
• sensing the incident light using a second group of gray color filters disposed to transmit spectral energy in at least the near-infrared (IR) spectrum, the gray color filters being disposed to transmit spectral energy in the red, green, and blue colors of the visible spectrum at 30% intensity and transmit spectral energy of the infrared spectrum at wavelengths above about 790 nm;
• and
• generating output signals at each pixel element of the digital image sensor as pixel data representing an image of a scene.