Imaging apparatus provided with imaging device having sensitivity in visible and infrared regions
An imaging apparatus includes: a first pixel which receives both visible light and infrared light, and a second pixel which receives infrared light, both pixels being formed on an imaging device; an infrared light component estimation unit which estimates, based on spectral characteristics of light received by the first pixel and spectral characteristics of light received by the second pixel, a magnitude of an infrared light component contained in a signal outputted from the first pixel from a signal outputted from the second pixel; and a subtraction unit which subtracts the estimated infrared light component from the signal outputted from the first pixel.
1. An imaging apparatus, comprising:
a first pixel which receives both visible light and infrared light;
a second pixel which receives infrared light;
a subtraction unit which subtracts from a signal outputted from the first pixel a signal obtained by multiplying a signal outputted from the second pixel by a coefficient K, where 0≦K≦1; and
a determination unit which variably controls, based on a ratio of a magnitude of the signal outputted from the second pixel to a magnitude of the signal outputted from the first pixel, the value of the coefficient K to be multiplied by the signal outputted from the second pixel in the subtraction unit between 0 and 1.
2. The imaging apparatus according to claim 1 , wherein the determination unit sets the value of the coefficient K to be multiplied by the signal outputted from the second pixel such that the higher the illuminance when an image is taken, the higher the value.
3. The imaging apparatus according to claim 1 , wherein the subtraction unit separately subtracts the signals obtained by multiplying the signal outputted from the second pixel by the coefficient K for a luminance component and by the coefficient K for a color component, from the signal outputted from the first pixel, and
the determination unit sets the value of the coefficient K for a luminance component to be lower than the value of the coefficient K for a color component.
4. The imaging apparatus according to claim 2 , wherein the subtraction unit separately subtracts the signals obtained by multiplying the signal outputted from the second pixel by the coefficient K for a luminance component and by the coefficient K for a color component, from the signal outputted from the first pixel, and
the determination unit sets the value of the coefficient K for a luminance component to be lower than the value of the coefficient K for a color component.
5. The imaging apparatus according to claim 1 , wherein the first pixel and the second pixel are formed on an identical imaging device.
6. The imaging apparatus according to claim 2 , wherein the first pixel and the second pixel are formed on an identical imaging device.
7. The imaging apparatus according to claim 3 , wherein the first pixel and the second pixel are formed on an identical imaging device.
8. The imaging apparatus according to claim 4 , wherein the first pixel and the second pixel are formed on an identical imaging device.
9. The imaging apparatus according to claim 1 , wherein the determination unit sets the value of the coefficient K such that the higher the ratio of the magnitude of the signal outputted from the second pixel to the magnitude of the signal outputted from the first pixel, the lower the value.
10. The imaging apparatus according to claim 9 , wherein the determination sets the value of the coefficient K to 0 when the ratio of the magnitude of the signal outputted from the second pixel to the magnitude of the signal outputted from the first pixel is higher than an higher reference value and sets the value to 1 when the ratio is lower than a lower reference value.