Head-up display with magnetic field speed detecting means

Claim 1

A vehicle head-up display for correctly displaying instant information values at an area visible to the driver in the central portion on the windshield of a vehicle, said display comprising: an electromagnetic inducer for detecting the changes of magnetic field generated by a plurality of magnetic force generators so as to sense an electromagnetic signal; the magnetic force generators secured on the wheel transmission shaft of the wheels for measuring the speed of the vehicle in conjunction with the sensing by the electromagnetic inducer; a counting circuit device comprising microprocessor IC and an interface circuit, which receives the electromagnetic signal via a signal line so as to calculate the speed of the vehicle; a projection display comprising a transmissive lens of a particular magnification, a fluorescent display lamp, a colored film having a transmissivity of only 70%, a dark colored transparent shield, a housing, a base, and an angle adjustment knob wherein the horizontal image displayed on the fluorescent display lamp is double-refracted by said transmissive lens and projected onto the windshield through said colored film and then reflected to form into the correct image; a function control box connecting to said projection display via a control function line for transferring the control signal to said counting circuit device, said function control box having a control panel with touch control keys for setting the contents of the informations to be displayed; and a light colored transparent displaying film having coated with hydrogel for displaying the image while preventing double images and the interference by the light rays coming from outside the vehicle.