Optical sensor device to be installed on board a motor-vehicle for aid in driving and/or for automatic activation of systems provided on the motor-vehicle

• US 7,365,303 B2
• Filed: 09/18/2006
• Issued: 04/29/2008
• Est. Priority Date: 10/21/2005
• Status: Expired due to Fees

• Current Assignee: C.R.F. Societa Consortile Per Azioni
• Original Assignee: Cefla Societa' Cooperativa
• Inventors: Pallaro, Nereo
• Primary Examiner(s): Le; Que Tan
• Assistant Examiner(s): Yam; Stephen
• Application Number:
  US11/522,342
• Publication Number:
  US 20070090311A1
• Time in Patent Office: 589 Days
• Field of Search: 250/573, 250/574, 250/575, 250/221, 250/208.1, 250/227.25, 348/148, 340/602
• US Class Current: 250/221
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60R 1/00 Optical viewing arrangements; Real-time viewing arrangements for drivers or passengers using optical image capturing systems, e.g. cameras or video systems specially adapted for use in or on vehicles
• CPC Class Codes: B60R 2300/106 using night vision cameras
• CPC Class Codes: B60R 2300/108 using 'non-standard' camera systems, e.g. camera sensor used for additional purposes i.a. rain sensor, camera sensor split in multiple image areas
• CPC Class Codes: B60R 2300/8053 for bad weather conditions or night vision
• CPC Class Codes: B60R 2300/8093 for obstacle warning
• CPC Class Codes: B60S 1/0822 characterized by the arrangement or type of detection means
• CPC Class Codes: B60S 1/0844 including a camera
• CPC Class Codes: B60S 1/0885 the sensor being integrated in a rear-view mirror module
• CPC Class Codes: B60S 1/0888 characterized by the attachment of the elements in a unit
• CPC Class Codes: G01J 1/02 Details
• CPC Class Codes: G01J 1/0271 Housings; Attachments or accessories for photometers
• CPC Class Codes: G01J 1/04 Optical or mechanical part supplementary adjustable parts
• CPC Class Codes: G01J 1/0411 using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
• CPC Class Codes: G01J 1/0437 using masks, aperture plates, spatial light modulators, spatial filters, e.g. reflective filters
• CPC Class Codes: G01J 1/4228 arrangements with two or more detectors, e.g. for sensitivity compensation
• CPC Class Codes: G01N 2021/4709 Backscatter
• CPC Class Codes: G01N 21/538 for determining atmospheric attenuation and visibility
• CPC Class Codes: G01S 7/4811 common to transmitter and receiver
• CPC Class Codes: G06V 20/56 exterior to a vehicle by using sensors mounted on the vehicle
• CPC Class Codes: H04N 23/55 : Optical parts specially adapted for electronic image sensors; Mounting thereof

Abstract

An optical sensor device that can be installed on board a motor vehicle for aid to driving and/or for automatic activation of one or more on-board systems according to the environmental conditions detected comprises a sensor module including an array of the CCD or CMOS type, the sensitive area of which is split into sub-areas dedicated to different functions, which are separate from one another and set at a distance apart, and located adjacent to the four vertices of the sensitive area of the array.

Claims

1. An optical sensor device of the type comprising:

an optical sensor in the form of CCD or CMOS array, having a sensitive area in which a number of sub-areas is defined, each designed for a specific optical function corresponding to monitoring of the scene in front of a motor vehicle and/or to detection of environmental parameters; and

a plurality of optical systems with different directions of the optical axis and/or fields of vision, designed to send optical signals to respective sub-areas of the sensitive area of said array in order to perform the aforesaid functions,

in which at least some of said sub-areas are defined by different and separate portions of the sensitive area of said array dedicated to different optical functions, and

in which said different and separate portions of the sensitive area of the array include at least;

a first portion of the top part of the sensitive area, defining a first sub-area for detection of fog in front of the motor vehicle;

a second and different portion of the sensitive area, defining a second sub-area, for detection of a twilight condition;

a bottom portion of the sensitive area, defining a third sub-area, separated from said first sub-area and from said second sub-area, for monitoring the scene in front of the motor vehicle;

a further portion of the top part of the sensitive area, defining a fourth sub-area different and separate from the first, second and third sub-areas, for detecting the presence of raindrops or mist on the windscreen or on the rear window of the motor vehicle;

wherein the plurality of optical systems comprises

a first optical system for conveying optical signals on said first sub-area for detection of fog, including a first light emitter for emitting light in the direction of the space in front of the motor vehicle, a receiver for receiving light scattered by the fog possibly present in front of the motor vehicle, and optical means for directing the light received only on said first sub-area of the sensitive area of said array; and

a second optical system, a third optical system and a fourth optical system provided for directing optical signals on said second, third and fourth sub-areas of the sensitive area of said array, respectively for detection of a twilight condition, for monitoring the scene in front of the motor vehicle, with particular reference to a condition in which the vehicle crosses another vehicle coming in the opposite direction or to a condition of passing through a tunnel, and for detection of raindrops or of mist on the window of the motor vehicle,

said optical sensor device being characterized in that;

said first, second, third and fourth sub-areas of the sensitive area of the array occupy portions that are separate and at a distance from one another of the sensitive area of the array, adjacent, respectively, to four different vertices of the sensitive area of the array;

said array is supported by a plate forming part of a sensor module incorporating at least part of the aforesaid optical systems;

said sensor module is mounted within a supporting structure;

said supporting structure supports the first emitter dedicated to the function of detecting fog, and a second emitter dedicated to the function of detecting rain and/or mist on the window of the motor vehicle;

the first optical system is oriented according to an axis directed upwards and towards a side of the motor vehicle, not orthogonal to the windscreen, according to a cone that crosses the cone of lighting of first emitter in an area located beyond the windscreen;

the third optical system comprises at least one lens having an optical axis parallel to the direction of travel;

the second optical system comprises an optical fibre with a front end oriented upwards and on a side with respect to the direction of travel of the vehicle, and a rear end, associated to which is a lens for causing the outcoming light beam to converge on the respective sub-area of the array; and

the fourth optical system comprises, at one end, a first lens facing the window of the motor vehicle, having its optical axis perpendicular to the window, and, at the other end, a second lens having its optical axis orthogonal to the array, and optical means set between said lenses for deflecting the beam coming from the first lens towards the second lens,

the aforesaid optical components being mounted within a support fixed on said rear plate bearing the array that constitutes therewith the aforesaid sensor module.

2. The sensor device according to claim 1, wherein, downstream of the first optical system optical means, an optical filter and one or more diaphragms are provided.

3. The sensor device according to claim 1, wherein, downstream of the third optical system at least one lens, are set a further lens and a diaphragm for limiting the cross section of the beam coming from the optical system that is directed towards the respective sub-area of the array, a further diaphragm being set between the two lenses.

4. The sensor device according to claim 1, wherein the second optical system is a biconvex lens.

5. The sensor device according to claim 1, wherein the first and second emitter devices are LED sources in the near infrared.

6. The sensor device according to claim 1, wherein the supporting structure of the sensor module comprises two separate supporting plates, screwed together and to the rear plate bearing the sensor array, a first of said supporting plates carrying the third optical system at least one lens, the fourth optical system second lens, and the second optical system lens, the second supporting plate carrying the remaining optical components and incorporating, a casing for the fourth optical system, which comprises, in addition to the first lens, two further lenses set in series downstream of the first lens, and a total-internal-reflection prism that deflects the beam coming from said further lenses towards the second lens at the end of the system facing the array of the sensor.

7. The sensor device according to claim 6, wherein set between the rear plate bearing the array and the aforesaid supporting plates are spacers selected for focusing of the system.

8. The sensor device according to claim 1, wherein the third optical system comprises an optical microzoom.

9. The sensor device according to claim 1, wherein the array is of the CMOS type with logarithmic response.

10. The sensor device according to claim 1, wherein the array is of the colour-CMOS type.

11. The sensor device according to claim 1, wherein the sensor device is associated to an electronic control unit designed to activate automatically one or more on-board systems of the motor vehicle as a function of the signals received from said sensor device.