Registers – Fare registers – Cab-fare indicating
Patent
1986-02-25
1988-12-06
Fuller, Benjamin R.
Registers
Fare registers
Cab-fare indicating
235 29A, 235 45, 350338, 361390, 361400, 439629, G07B 1300
Patent
active
047897740
DESCRIPTION:
BRIEF SUMMARY
The invention is directed to a multi digit electronic display device illuminatable by means of light sources, for instance for a taximeter for display of a fare to be paid and possibly accumulating surcharges, as well as for overlay of storage- or tariff data.
Electronic display devices for presentation of numerals and characters have been known for years and are of differing structure and operation not lastly because of the utilization manner. A widely used embodiment form is constituted by the liquid crystal display (LCD), which in one typical application case is utilized as a 7-segment display in apparatus with digital display. The basic principle of a liquid crystal cell consists as is well known in that two glass plates are covered at the faces facing each other with transparent conductive coatings, which are masked according to the desired display configuration. In a cell between the glass plate there is located a nematic, crystalline liquid, which under the influence of the electrical field forms zones with different refraction index when a voltage is applied to the thin film electrodes. Depending on the design of the structure of the one transparent electrode the liquid crystal cell can be utilized for the presentation of numerals, letters or other communication characters. Depending on the type of operation one differentiates between reflection operation, transmitted light or transmitted operation and a transflective operation. In the reflection operation the illumination of the reflective display occurs by the existing ambient light, by arranging a mirror on the rear side of the cell. In transmitted light operation of a liquid crystal cell the light source is located on the rear side behind the display element. By arranging a diffuser between the light source and the liquid crystal cell one achieves that the light is absorbed as ideally as possible.
In transflective operation a semi-transparent mirror is located on the rear side of the liquid crystal cell, which on the one hand reflects the ambient light, on the other hand however is sufficiently transparent for light, so that the liquid crystal cell is illuminated by the switched-on light source with diffuser. A change between the thereby effective operational modes with transmitted light and reflection occurs automatically depending on the illumination intensity of the ambient field. This means in case of an ambient field illumination intensity which is higher than the built-in background illumination, a reflection operation is set up, in the reverse case the liquid crystal cell works by transmitted light operation. Such a liquid crystal display is suitable for such application cases, where a background illumination is continuously switched on but also for display types, where the background illumination can be switched by the observer in case of necessity. The transfluxor operation of a liquid crystal display with permanently switched-on background illumination in the operating state affords the considerable advantage through the property of an automatic change onto the optimum type of operation depending on the momentary illumination intensity, that the symbols displayed appear always with the best possible contrast effect against the background. Thereby the readability of a display field remains constant even with constantly changing ambient light conditions. To that extent this property speaks in favor of an application in the motor vehicle as a taximeter display, if one achieves satisfaction of the requirements in the taxi vehicle by a sensible arrangement and design of the display field.
It is the task of the invention to design and arrange a multi-digit electronic device for a taximeter in such a way that it can be completed out of simple parts and can be plugged into a printed circuit board by means of suitable connection means, whereby at the same time the actuation lines are connectible with the printed circuit board and a space saving arrangement for optimum illumination of the displayable information is assured.
A solution of this t
REFERENCES:
patent: 3991463 (1976-11-01), Squitieri et al.
patent: 4012117 (1977-05-01), Lazzery
patent: 4059916 (1977-11-01), Tachihara et al.
patent: 4126383 (1978-11-01), Doriguzzi et al.
patent: 4209688 (1980-06-01), Kelch
patent: 4247928 (1981-01-01), Dorfman
patent: 4357061 (1982-11-01), Crosby
patent: 4422728 (1983-12-01), Andreaggi
patent: 4574189 (1986-03-01), Adams et al.
patent: 4616295 (1986-10-01), Jewell et al.
Koch Siegfried
Scholl Hans-Peter
Fuller Benjamin R.
Mannesmann Kienzle GmbH
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