Submitted byMadhavareddy.TRoll.no:-11603653Sec:-1605 submitted to Himanshu Aarora sir

Night vision technology in auto-mobiles

Introduction An automotive night vision system uses a thermographic camera to increase a driver's perception and seeing distance in darkness or poor weather beyond the reach of the vehicle's headlights. Such systems are offered as optional equipment on certain premium vehicles. The first introduction was in 2000 on Cadillac Deville.

What makes humans enable to view objects? When a light

projects on any object the object reflects the light. This reflected light by the object enables humans to view the object.

With this humans are able to distinguish the object from others, with respect to its properties like colour ,size, shape, etc.

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Types of night vision & their

workingCategorized by generationsEach substantial change NVT establishes a new

generationCategorized into: Generation-0 Generation-1 Generation-2 Generation-3 Generation-4

Generation-0 Created by US Army Uses active infrared A projection unit called IR illuminator

is attached Full moon operation Use anode in conjunction with cathode to accelerate the electrons Problems –acceleration causes distortion of image as well as reduction of life of the tube Also, it was quickly duplicated by the

hostile nations

Figure illustrates Generation 1

Night vision technology.

Generation-1 (1960’s)

Uses passive infraredUses ambient light provided by the moon and the stars

Don’t require a source of projected infrared light

Don’t work well on cloudy or moonless nightsOne quarter moon operationUses same image-intensifier tube technology as Generation-0

Same problems as faced by the Generation-0

Figure illustrates Generation 2 Night vision technology.

Generation-2 (1970’s)

Offer improved resolution and performance over Generation-1 devices

Considerably more reliableAble to see in extreme low light conditions due to the addition of microchannel plate(MCP) to the image-intensifier tube

The images are less distorted and brighter

Generation-3 (1990’s)

Currently used by the US ArmyBetter resolution and sensitivityPhotocathode is made up of Gallium Arsenide

MCP is coated with an ion barrierTube life is increased

Generation-4 (2000’s)

Known as “filmless and gated” technology

Shows significant improvement in both high- and low-level light environments

No ion barrier in MCPResponds quickly to different lightning conditions

Reduced background noiseEnhances signal to noise ratioImages are less distorted and brighter

Thermal imaging This technology operates by capturing upper portion of the infrared light spectrum, which is emitted as heat

Hotter objects emit more of this light than the cooler objects

These elements then create a thermogram

Thermogram electric pulses display data

The basic components of a Thermal-imaging system

Thermal imaging

Thermal imaging lets you see again.

It is quite easy to see everythingduring the day...

...but at night, you can seevery little.

Image Enhancement

Image EnhancementIt is also known as Image intensificationRelies on image intensifier tube to collect an amplify infrared and visible light

Lens captures the light which is then sent to image intensifier tube

It has photocathode that converts photons into electrons

When electrons pass through MCP ,more electrons are presented

This causes chain reaction where atoms are released

Electrons reach phosphor screen and photons are released

Those phosphor create green image

Display type in night vision technology

• Instrument cluster using a high resolution liquid-crystal display (LCD), newest type

• Navigation system or information screen, least expensive and with display's location further away from driver's field of vision (used exclusively by BMW, and the W212 E-class)

• Windshield via head-up display, earliest type, dimmer knob can reduce brightness, display nearest to driver's line of sight

There are two types of systems, either passive or active systems, both have advantages and disadvantages when compared to the other.

Navigation system or information screen

Windshield via head-up display

Instrument cluster

Types of night vision systems adapted in automobiles

Passive systemsActive systems

Passive systems

Passive infrared systems do not use an infrared light source, instead they capture thermal radiation already emitted by the objects, using a thermographic camera.

Pros: greater range of about 300 meters or 1,000 feet, higher contrast for living objects

Cons: grainy, lower resolution image, works poorly in warmer weather conditions, larger sensor

Cars that used passive systems:1. Audi R8

Night Vision Assistant infrared camera visible on Audi A8 grill, right circleNight Vision Assistant was introduced in 2010 on the Audi A8. It uses a thermal imaging camera behind the four rings at the front of the car which can "see" 300 meters (984 ft) ahead. The display in the instrument cluster highlights humans with yellow markings. More importantly, the computer can determine if the person on the road moves in a way that could lead to a collision with the car. In that case the pedestrian is being marked in red color and the driver of the car receives an audible warning. 2013 update added animal detection and Pedestrian Marker Lights.

Infrared camera

2) BMW 7 Series (E65)

BMW Night Vision introduced in 2005 on the BMW 7 Series (E65). This system processes far infrared radiation, which minimizes non-essential information placing a greater emphasis on pedestrians and animals, allows for a range of 300 meters or nearly 1,000 feet, and avoids "dazzle" from headlights, road lights and similar intense light sources.

3)Cadillac

First worldwide series production automotive night vision on 2000 Cadillac Deville: Night

Vision, This system was developed with Raytheon and worked by using a passive infrared

sensor camera mounted behind the vehicle's grille. Infrared radiation is picked up by the sensor,

processed by computer and then displayed on the windshield using a head-up display

4)Honda

In 2004: Honda introduced first worldwide system with pedestrian detection on

redesigned Honda Legend: Intelligent Night Vision. It detected far infrared radiation.

The pedestrian detection feature alerted the driver with an audio warning and visually

enclosed the pedestrian in a box on the display which was presented via head-up

display. The night vision system uses a separate heads up type display projected on the

center bottom of the windshield.

1)Mercedes-Benz

Night View Assist infrared projector visible next to Bi-Xenon HID main headlight, Mercedes-Benz S-Class (W221)It was the first system to use the instrument cluster's LCD as a display.2009: Night View Assist Plus added a pedestrian detection function calling the revised system on the redesigned Mercedes-Benz E-Class (W212) and refreshed S-class, however, the E-class uses the navigation screen's display.

Night View Assist infrared projector visible next to Bi-Xenon HID main headlight, Mercedes-Benz S-Class (W221)

Cars that used Active systems:

2)ToyotaIn 2002 Toyota Night View was the first worldwide series production active automotive night vision system, introduced on the Toyota Landcruiser Cygnus or Lexus LX470. This system uses the headlight projectors emitting near infrared light aimed like the car's highbeam headlights and a CCD camera then captures that reflected radiation, this signal is then processed by computer which produces a black-and-white image which is projected on the lower section of the windshield.

Night View system on the 2003 Lexus LX 470