Optical waveguides – With optical coupler – Input/output coupler
Patent
1996-03-04
1997-02-25
Healy, Brian
Optical waveguides
With optical coupler
Input/output coupler
385 32, 385 38, 385 39, 385 49, 385123, 385125, 385147, 385901, 362 31, 362 32, 362259, 362260, 40546, 40547, 372109, G02B 626, F21V 704, G09F 1318
Patent
active
056066341
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a display unit. It more particularly relates to the field of electric, light signs and markings. For the latter, use has hitherto been made of photoemissive diodes or lamps.
2. Discussion of the Background
It has been forbidden to use lasers, which emit coherent electromagnetic rays, which can give rise to serious injuries to the eyes of observers.
In order to provide protection against the lasers, it is known to use materials able to absorb laser beams, but if in this way users are protected, they are inter alia also deprived of visible information concerning the presence of laser beams.
In order to reveal the presence of a laser beam, use is presently made of complex and costly means requiring electric power to operate. Such means consist e.g. of pilot lamps, photodetectors, electronic cameras and means for measuring power by absorption by a black body.
SUMMARY OF THE INVENTION
The present invention aims at obviating the above disadvantages by proposing a display unit using a laser beam and which permits the display of light or luminous informations and in particular the indication of the presence of a laser beam.
The unit according to the invention supplies an information in visible light, without any danger for observers, said unit being manufacturable in a simple and inexpensive manner and, in numerous embodiments, requires no electric power supply in order to operate.
More specifically, the present invention relates to a display unit, characterized in that it comprises: incoherent light, said conversion element being placed in front of the optical waveguide and and which is transparent to the visible and incoherent light and able to stop the residual laser beam liable to emerge from the conversion element, element.
According to a preferred embodiment of the unit according to the invention, said unit also comprises means for applying stresses to the optical waveguide in order to bring about for the latter laser beam losses and the conversion element is exposed to said laser beam losses.
According to an embodiment of the unit according to the invention, the waveguide is curved so as to form at least one sign and the conversion element is placed in front of said sign.
According to another embodiment, the unit according to the invention also comprises a mask, which is opaque to the visible and incoherent light and is positioned in front of the conversion element and perforated by at least one hole forming a sign.
The conversion element can be solid. However, the conversion element can also be a liquid. In this case, the optical waveguide can be placed in said liquid.
BRIEF DESCRIPTION OF THE DRAWINGS
In an embodiment of the invention, the conversion element forms a cladding around the optical waveguide.
The stresses applied to the optical waveguide can be constant as a function of time, or conversely can vary in time.
The conversion element can be of a non-persistent fluorescent material or a persistent phosphorescent material (with memory effect).
The invention is described in greater detail hereinafter relative to nonlimitative embodiments and with reference to the attached drawings, wherein show: invention using various conversion elements. in the form of plates.
FIG. 4 A partial, diagrammatic view of another embodiment using conversion elements forming signs.
FIG. 5 A partial, diagrammatic view of another embodiment using a conversion element in cladding form.
FIG. 6 A diagrammatic view of another embodiment using a liquid conversion element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The unit according to the invention and which is diagrammatically shown in FIG. 1 comprises: beam 4, diagrammatically represented by an arrow in FIG. 1 and which give rise to laser beam losses on the part of the guide 2, guide 2, into a visible and incoherent light and by the conversion element 8 and able to stop the residual laser beam liable to emerge from said conversion element.
Therefore the visible and incoheren
REFERENCES:
patent: 4011403 (1977-03-01), Epstein et al.
patent: 4640592 (1987-02-01), Nishimura et al.
patent: 4845596 (1989-07-01), Mouissie
patent: 4907132 (1990-03-01), Parker
patent: 4961617 (1990-10-01), Shahidi et al.
patent: 5016956 (1991-05-01), Gasparaitis et al.
patent: 5036435 (1991-07-01), Tokuda et al.
patent: 5042892 (1991-08-01), Chiu et al.
patent: 5249105 (1993-09-01), Koizumi
patent: 5400224 (1995-03-01), DuNah et al.
patent: 5448582 (1995-09-01), Lawandy
patent: 5461548 (1995-10-01), Esslinger et al.
patent: 5488696 (1996-01-01), Brosnan
patent: 5528399 (1996-06-01), Izumi et al.
patent: 5542016 (1996-07-01), Kaschke
patent: 5544268 (1996-08-01), Bischel et al.
Commissariat a l''Energie Atomique
Healy Brian
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