Night-vision imaging apparatus, control method of the same, and headlight module

• US 7,579,593 B2
• Filed: 07/06/2007
• Issued: 08/25/2009
• Est. Priority Date: 07/25/2006
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Ueda, Daisuke, Onozawa, Kazutoshi
• Primary Examiner(s): Porta; David P
• Assistant Examiner(s): Taningco; Marcus H
• Application Number:
  US11/774,088
• Publication Number:
  US 20080029701A1
• Time in Patent Office: 781 Days
• Field of Search: 250/332
• US Class Current: 250/332
• CPC Class Codes: B60Q 1/0023 the element being a sensor, e.g. distance sensor, camera
• CPC Class Codes: G01S 17/89 for mapping or imaging
• CPC Class Codes: G01S 17/931 of land vehicles
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G01S 7/4918 Controlling received signal intensity, gain or exposure of sensor
• CPC Class Codes: G01S 7/493 Extracting wanted echo signals
• CPC Class Codes: G01S 7/499 using polarisation effects
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H01L 27/148 Charge coupled imagers individual charge coupled devices H01L29/765

Abstract

The invention provides a night-vision imaging apparatus including: a light emission unit that emits infrared light; a solid-state imaging device that converts the infrared light into a first signal; a light-emission control unit that allows the light emission unit to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and an extraction unit that extracts, according to the first modulation, a signal corresponding to the infrared light emitted by the light emission unit from the first signal.

Claims

1. A night-vision imaging apparatus, comprising:

a light emitter operable to emit infrared light;

a solid-state imager operable to convert the infrared light into a first signal;

a light-emission controller operable to allow said light emitter to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and

an extractor operable to extract, according to the first modulation, a signal corresponding to the infrared light emitted by said light emitter from the first signal, wherein said light emitter is operable to emit first infrared light and second infrared light,

said solid-state imager includes;

a first pixel which converts the first infrared light into the first signal; and

a second pixel which converts the second infrared light into a second signal,

said light-emission controller being operable to allow said light emitter to emit the first infrared light which is modulated according to the temporally pseudo-random first modulation, and is operable to allow said light emitter to emit the second infrared light which is modulated according to a temporally pseudo-random second modulation different from the first modulation,

said extractor being operable to extract, according to the first modulation, a signal corresponding to the first infrared light emitted by said light emitter from the first signal, and is operable to extract, according to the second modulation, a signal corresponding to the second infrared light emitted by said light emitter from the second signal.

2. The night-vision imaging apparatus of claim 1, said night-vision imaging apparatus further comprising:

a pulse generator operable to generate a pulse signal modulated in a temporally pseudo-random manner using a spread spectrum system,

wherein said light-emission controller is operable to allow said light emitter to emit the infrared light at a timing of change of the pulse signal, and

said extractor is operable to extract the signal corresponding to the infrared light emitted by said light emitter from the first signal at the timing of change of the pulse signal.

3. The night-vision imaging apparatus of claim 1,

wherein the first modulation and the second modulation are temporally opposite to each other.

4. The night-vision imaging apparatus of claim 1,

wherein said light emitter includes:

a first infrared LED which emits the first infrared light which is infrared light at a first wavelength; and

a second infrared LED which emits the second infrared light which is infrared light at a second wavelength different from the first wavelength,

said first pixel converts infrared light at the first wavelength into the first signal, and

said second pixel converts infrared light at the second wavelength into the second signal.

5. The night-vision imaging apparatus of claim 1,

wherein said light emitter is operable to emit the first infrared light linearly polarized in a first direction, and the second infrared light linearly polarized in a second direction different from the first direction,

said first pixel converts, into the first signal, the infrared light linearly polarized in the first direction, and

said second pixel converts, into the second signal, the infrared light linearly polarized in the second direction.

6. The night-vision imaging apparatus of claim 5,

wherein the first direction is orthogonal to the second direction.

7. The night-vision imaging apparatus of claim 5,

wherein said light emitter includes:

a first infrared LED which emits infrared light;

a first polarizer operable to linearly polarize, in the first direction, the infrared light emitted by said first infrared LED;

a second infrared LED which emits infrared light; and

a second polarizer operable to linearly polarize, in the second direction, the infrared light emitted by said second infrared LED.

8. The night-vision imaging apparatus of claim 5,

wherein said light emitter includes:

an infrared LED which emits infrared light; and

a polarizer operable to linearly polarize, in one of the first direction and the second direction, the infrared light emitted by said infrared LED.

9. The night-vision imaging apparatus of claim 8,

wherein said polarizer includes:

a polarization device operable to linearly polarize the infrared light emitted by said infrared LED; and

a rotator operable to rotate said polarization device to change a direction polarized by said polarization device to one of the first direction and the second direction.

10. The night-vision imaging apparatus of claim 9,

wherein said rotator is operable to rotate said polarization device at a blanking period.

11. The night-vision imaging apparatus of claim 8,

wherein said polarizer includes:

a polarization device operable to linearly polarize the infrared light emitted by said infrared LED;

a liquid crystal device operable to shift a phase of the infrared light linearly polarized by said polarization device; and

a voltage applicator operable to change a voltage to be applied to said liquid crystal device to change an amount of shift of the phase shifted by said liquid crystal device.

12. The night-vision imaging apparatus of claim 11,

wherein said voltage applicator is operable to change the voltage to be applied to said liquid crystal device at a blanking period.

13. The night-vision imaging apparatus of claim 5, said night-vision imaging apparatus further comprising:

a detector operable to determine whether an intensity of at least one of the first signal and the second signal is at least equal to a predetermined intensity; and

a light attenuator operable to attenuate infrared light received by said solid-state imager when said detector determines that the intensity of at least one of the first signal and the second signal is at least equal to the predetermined intensity.

14. The night-vision imaging apparatus of claim 13,

wherein said light attenuator includes:

a polarization device operable to transmit infrared light having a predetermined linear polarization component; and

a rotator operable to rotate said polarization device to attenuate the infrared light received by said solid-state imager.

15. The night-vision imaging apparatus of claim 13,

wherein said light attenuator includes:

a liquid crystal device operable to shift a phase of infrared light received by said solid-state imager; and

a voltage applicator operable to change a voltage to be applied to said liquid crystal device to change an amount of shift of the phase shifted by said liquid crystal device.

16. The night-vision imaging apparatus of claim 1, said night-vision imaging apparatus further comprising

a white LED which emits white light,

wherein said light emitter is operable to light up when said white LED is on.

17. The night-vision imaging apparatus of claim 1,

wherein said light emitter is used as a light source for a high beam.

18. A night-vision imaging apparatus, comprising:

a light emitter operable to emit infrared light;

a solid-state imager operable to convert the infrared light into a first signal;

a light-emission controller operable to allow said light emitter to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and

an extractor operable to extract, according to the first modulation, a signal corresponding to the infrared light emitted by said light emitter from the first signal,

wherein said solid-state imager includes;

a first pixel which converts the infrared light into the first signal; and

a second pixel which converts light at a visible wavelength into a second signal.

19. A night-vision imaging apparatus, comprising:

a light emitter operable to emit infrared light;

a solid-state imager operable to convert the infrared light into a first signal;

a light-emission controller operable to allow said light emitter to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and

an extractor operable to extract, according to the first modulation, a signal corresponding to the infrared light emitted by said light emitter from the first signal,

wherein said solid-state imager includes;

a first pixel which has a sensitivity at a wavelength of infrared light;

a second pixel which has a sensitivity at a wavelength of red light;

a third pixel which has a sensitivity at a wavelength of green light; and

a fourth pixel which has a sensitivity at a wavelength of blue light.

20. A night-vision imaging apparatus, comprising:

a light emitter operable to emit infrared light;

a solid-state imager operable to convert the infrared light into a first signal;

a light-emission controller operable to allow said light emitter to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and

an extractor operable to extract, according to the first modulation, a signal corresponding to the infrared light emitted by said light emitter from the first signal,

wherein said solid-state imager includes a plurality of pixels, and

each of said pixels includes;

a light receiver operable to receive at least one of infrared light and visible light; and

a light transmitting film having a refractive index distribution formed on said light receiving device.

21. A headlight module, comprising:

a light emitter operable to emit infrared light;

a solid-state imager operable to convert the infrared light into a first signal;

a light-emission controller operable to allow said light emitter to emit the infrared light which is modulated according to a temporally pseudo-random first modulation; and

an extractor operable to extract, according to the first modulation, a signal corresponding to the infrared light emitted by said light emitter from the first signal,

wherein said light emitter includes;

a first infrared LED which emits first infrared light; and

a second infrared LED which emits second infrared light,

said solid-state imager includes;

a first pixel which converts the first infrared light into the first signal; and

a second pixel which converts the second infrared light into a second signal,

said light-emission controller being operable to allow said first infrared LED to emit the first infrared light which is modulated according to the temporally pseudo-random first modulation, and is operable to allow said second infrared LED to emit the second infrared light which is modulated according to a temporally pseudo-random second modulation different from the first modulation, and

said extractor extracts, according to the first modulation, a signal corresponding to the first infrared light emitted by said light emitter from the first signal, and extracts, according to the second modulation, a signal corresponding to the second infrared light emitted by said light emitter from the second signal,

said headlight module further comprising;

a first module which includes said first infrared LED and said second pixel and is installed in one of a right front side and a left front side of a vehicle; and

a second module which includes said second infrared LED and said first pixel and is installed in other than the right front side and the left front side of the vehicle.