Imaging device

• US 10,298,856 B2
• Filed: 08/02/2016
• Issued: 05/21/2019
• Est. Priority Date: 08/27/2015
• Status: Active Grant

• Current Assignee: Clarion Co., Ltd. (Faurecia SA)
• Original Assignee: Clarion Co., Ltd. (Faurecia SA)
• Inventors: Kojima, Takahide
• Primary Examiner(s): Gee, Alexander
• Application Number:
  US15/755,818
• Publication Number:
  US 20180332209A1
• Time in Patent Office: 1,022 Days
• CPC Class Codes: H04N 23/00 Cameras or camera modules comprising electronic image sensors; Control thereof
• CPC Class Codes: H04N 23/11 for generating image signals from visible and infrared light wavelengths
• CPC Class Codes: H04N 23/12 with one sensor only
• CPC Class Codes: H04N 23/741 by increasing the dynamic range of the image compared to the dynamic range of the electronic image sensors
• CPC Class Codes: H04N 23/86 for controlling the colour saturation of colour signals, e.g. automatic chroma control circuits
• CPC Class Codes: H04N 25/11 Arrangement of colour filter arrays [CFA]; Filter mosaics
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 9/68 for controlling the amplitude of colour signals, e.g. automatic chroma control circuits H04N9/71, H04N9/73 take precedence; camera processing pipelines for controlling the colour saturation of colour signals H04N23/86
• CPC Class Codes: H04N 9/77 Circuits for processing the brightness signal and the chrominance signal relative to each other, e.g. adjusting the phase of the brightness signal relative to the colour signal, correcting differential gain or differential phase circuits for matrixing H04N9/67

Abstract

To obtain a color signal having a wide dynamic range (i.e., high sensitivity) and color reproducibility similar to human vision characteristics regardless of the amount of the near infrared components contained in light captured by an imaging device. The imaging device is configured to receive light which has transmitted through the filters selectively transmit light having different wavelengths from each other, to generate an output signal RAW0 by converting the received light using the image pickup element 102 having the plurality of pixels, and to remove, by a removal rate E (Rr) determined in accordance with the ratio Rr of near infrared light component calculated for each pixel, the near infrared light component for each pixel from the generated output signal RAW0, to thereby generate an infrared-separated signal (Ra, Ga, Ba).

Claims

1. An imaging device comprising:

an optical filter on which a plurality of filters is arranged in a predetermined manner, the plurality of filters including;

three types of filters configured to selectively transmit light of a visible light region having different wavelengths from each other and to have spectral transmittances equal to each other in a near infrared light region, and

one type of filter in which a spectral transmittance of the visible light region is expressed by a linear sum of the spectral transmittances of the three types of filters and which has a spectral transmittance equal to the spectral transmittances of the three types of filters in the near-infrared light region,

an image pickup element including a plurality of pixels which receive light transmitted through the optical filter, convert the received light into an output signal in accordance with luminance of incident light incident to each of the pixels, and output the output signal from each of the pixels;

a near infrared light ratio calculating part which calculates a ratio of near infrared light component contained in the output signal for each of the pixels; and

an infrared separating part which removes, by a removal rate determined in accordance with the ratio of the near infrared light component, the near infrared light component from each of the output signals for each of the pixels to generate an infrared-separated signal,

wherein the infrared separating part is configured to continuously change the removal rate such that the removal rate become zero (0) when the ratio of the near infrared light component is around 0% and when the ratio of the near infrared light component is around 100%.

2. The imaging device according to claim 1, wherein the infrared separating part is configured to remove the near infrared light component in accordance with the removal rate determined based on a near infrared light component removal rate table which stores the removal rate of the near infrared light component with respect to the ratio of the near infrared light component contained in the output signal.

3. A method of imaging, comprising:

arranging a plurality of filters in a predetermined manner, the plurality of filters including;

three types of filters configured to selectively transmit light of a visible light region having different wavelengths from each other and to have spectral transmittances equal to each other in a near infrared light region, and

one type of filter in which a spectral transmittance of the visible light region is expressed by a linear sum of the spectral transmittances of the three types of filters and which has a spectral transmittance equal to the spectral transmittances of the three types of filters in the near-infrared light region,

receiving light transmitted through the plurality of filters,

converting the received light into an output signal in accordance with luminance of incident light incident to each pixel and outputting signal from each pixel,

calculating a ratio of near infrared light component contained in the output signal for each pixel,

by a removal rate determined in accordance with the ratio of the near infrared light component, removing the near infrared light component from each of the output signals for each pixel to generate an infrared-separated signal, and

continuously changing the removal rate such that the removal rate become zero (0) when the ratio of the near infrared light component is around 0% and when the ratio of the near infrared light component is around 100%.