Transcript

Guide : Submitted by:

Mr. Vishal Sharma Dishant Arora

Submitted to: Roll no: ue85028

Mr. Sumit Buddhiraja ECE(7th-sem)

•A head-up display system projects an image directly onto the human retina with low-energy lasers or LCDs.

•A head up display was first used by USA military

in 1933

INTRODUCTION

•A HUD - Head Up Display - is a means of presenting information to the pilot in the line of their external forward vision which projects key flight instrument data onto a small ‘see-through’ screen positioned just in front of the pilot line of sight looking ahead out of the aircraft

•Head-Up Display also known as HUD, is any type of display that presents data without blocking the user's view.

ACCORDING TO REPERSENTAION: 2-D: The symbol or information presented in

HUD is in two dimensional

• 3-D HUD: The image or information seen by user on HUD screen is in three dimensional.

ACCORDING TO POSITION:

1) Fixed HUD- In which the user looks through a display element attached to the airframe or vehicle chassis.

•2) Helmet-mounted or head-mounted:

•In which the display element moves with the user's head.

•The user must wear a helmet or other headgear which is securely fixed to the user's head.

• HUDs have in common the following characteristics:

• The display element is largely transparent.• The information is projected with its focus at

infinity .• HUD must be compact and lightweight

• A computer to receive data and generate display symbology.

• An overhead unit to mount the cathode ray tube (CRT) which projects the assembled image onto the transparent display screen in front of the pilot.

• The transparent display screen - called a combiner - which is a ‘holographic optical element’ made of glass or plastic that reflects the projected image towards the pilot’s eyes without interfering with the passage of ambient light.

•A control panel to allow selection by the pilot of various display options and to enter data not received and integrated by the computer from aircraft sensors.

•An annunciator panel to provide HUD status and warning information.

• A typical human eye will respond to light of wavelengths from about 390 to 750 nm.

• When light encounters a material, it can interact with an object by some combination of reflection, absorption and transmittance with refraction.

• These interactions depend on the wavelength of the light and the nature of the material.

•Many substances are selective in their absorption of white light frequencies. They absorb certain portions of the visible spectrum, while reflecting others.

•The frequencies of the spectrum which are not absorbed are either reflected back or transmitted for our physical observation. This is what gives rise to color.

•The attenuation of light of all frequencies and wavelengths is due to the combined mechanisms of absorption and scattering.

In HUD system the light of some particular wavelength is fall on the screen, such that screen absorb or refract all other component of light and reflect light of only one color.

The human eye is most sensitive to green light so in HUD system green light is used for repersentation of image or information on the screen.

The working of HUD divided into four section:

Electronics Light source Scanners Optics

• Electronics acquire and process signals from an image or data source, such as a Web page or video camera.

• These signal come from sensors that are connect to HUD system for measuring altitude, direction , Angle of attack , radar signals, etc.

• The processed signals contain information for the intensity and mix of color .

• This information is stored in memory until needed.

• The data pass through a digital-to-analog converter that controls the light source.

• The light source consist of CRT, LASER,LED.

• Once the image has been rendered into memory, there is no need to recalculate it unless something has changed.

• In the scanned beam display headset the viewer sees an image when modulated signals from laser diodes sweep across the retina.

• A microcontroller in the visor selects the image from the view memory and passes it to digital to analog converters.

• These produce signals that Control lasers - red, green and blue-for a full color display.

• The modulated light passes to a tiny scanning mirror and then to a pupil expander that allows for eye movement by enlarging the image.

Optics section consist of: Collimating lens Folding mirror Combiner The most common means by which current HUDs

are implemented is to project the image onto a clear glass optical element ('combiner')

The image produce by combiner appear to be at opticaly infinity

•The pilot does not need to refocus eyes when switching between outside the enviroment and reading the HUD data

There are manily four type of combiner: Partially reflective Dichroic Catadioptric Holographic

• 2-Dimensional HUD

HUD is used in various fields for Military purpose

Aircrafts

HUD is also used in

Automobiles

Medical operations

Live news reading

Vedio gaming

• As with most hi-tech electronics, head-up displays are set to become smaller and lighter. Micro Optical is working towards a model that will look no different to a normal pair of glasses.

• In the near future, head-up displays will be available with wi fi and Bluetooth connectivity, allowing user's to surf the web and check their email on the move.

•Mapping will take on a new leash of life with augmented reality and GPS technology.

•Users will be able to see a map of their current location displayed right on top of the real thing. This will aid navigation in cities and countryside, allowing street names to appear on every road and virtual sign-posts to lead you to your destination.

REFERENCE

•www.iec.org

•www.wikipedia.com

•www.airbus.com

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