FR2516681A1 - EXCIMER FLUORESCENCE OPTICAL DEVICE - Google Patents

Abstract

A DISPLAY DEVICE USES ELECTRIC DISCHARGE PASSING THROUGH A GAS MIXTURE TO FORM AN EXCIMER WHICH EMITS FLUORESCENCE IN THE BLUE-GREEN REGION OF THE OPTICAL SPECTRUM.

Description

251668 1

  EXPERIMENTAL FLUORESCENCE DIGITAL DEVICE The invention of the invention is that of the devices of the invention. information in Emission of

light visiile.

Previous art = ur

  In the field of display devices used in

  its' Ln medium gaseous emitter, such as ampoules to

  neon, seven segment displays, indicator tubes,

  the standard gaseous mixture predominantly used in neon, often added with small amounts of other rare gases such as xenon or argon, which improve

  the electrical characteristics by the Penning effect These -

  1 nelanges e put in the region of the orange / red optical spectrum, towards the lower end of the response of the middle eye- The man of the art has long sought a gas or a gas mixture that emits in the green or blue region of the spectrum, in which the eye, especially

  if he has accommodated himself in the dark, is more sensitive.

  The most successful mixtures so far sought are those described in an article by G F Watson, Journal of Physics E 8, 981 (1975). One variant uses a gaseous mixture which is emitted in the ultraviolet, the ultraviolet ray

  being converted into visible light by means of a substance

  this light coated on one side of the glass containing the gas mixture This variant has the disadvantage

  light substance tends to reduce the reso-

  of the display device, because the light 3c emitted by the light source extends over a surface

  wider than the current drcharge in the

  Another variant is revealed in an article by 0 Sahni in the SID International Symposium Digest of

  1980, of April 1980, which describes a mi-

  gaseous age of nercury requiring a control of the temperature

  ture The need for limit temperature control

  especially the practical applications.

  In the laser technique, the emission in the green / green part of the spectrum has been produced by the exciter of lasers using gas mixtures under high pressure of the order of several atmospheres and a discharge with high electron density. at least 1014 electrons oar centimeter cutique A typical example is that described in the Journal of Chemical Physics by G Marowsky et al.

, 1153 - (1981).

Discovery of the invention

  The invention relates to a display device op-

  using an electric shock through a

  gaseous place, in which excited or ionized species

  produced from the constituents of the gas in the middle

  under the action of the discharge to form a molecule

  excimer emitting a fluorescent ray in the

  visible or ultraviolet spectrum of the electromagnetic spectrum

tick.

Brief description of the drawings

  Figure 1 illustrates an exploded view of a

  invention; F'igure 2 illustrates the variation with the wavelength of an embodiment of the invention at different pressures; Figure 3 illustrates the variation with the pressure of the amplitude of the pulse and the relative brightness of two different gaseous gases; and

  Figure 4 illustrates another achievement of the in-

vention.

  Best way to achieve the invention

  In the prior art, display devices op-

  tick, the most popular transmitter medium was neon, which is often used with low gas additions

  such as xenon or argon, and that emits in the rb-

  orange / red of the visible spectrum The emission of the

  neon is within the response range of an eye accom-

  MODEL IN THE LIGHT, but is dimly perceived by an eye accomodating in the darkness The men of the art have long sought for mixtures that would emit brilliantly in the visible region of the spectrum near the blue region.

  green in which a human eye accommodated in the otscuri-

  t & is more sensitive The prior art did not allow

  to achieve a reasonable degree of gloss in the spectral region dsir 6 e, except at the introductory price

of undesirable characteristics.

  Optical display devices used

  mercially use operating pressures

  below or reasonably close to atmospheric pressure

  pheric, so that an excessive reinforcement of large

  glass panels is not necessary; and use only

  moderate amounts of voltage and current

  so that an expensive supply of energy is not required

  These conditions are considerably different from

  operating conditions of the laser excimer

  its by high pressures and current densities

electronics and lifted.

  It has been found that it is possible to produce

  eximers (for the purpose of this patent, the term

  excimer will mean a homogenous excited molecular complex

  nuclear reactor and nuclear hetonuclear at a time) in a gaseous mixture with a reasonable yield using a

  pressure, voltages and currents appropriate to

  conventional plasma waters, thus making a

  optical display system using such a mixture of

  from a commercial point of view

  particular, in which the excimer Xe C 12 * is the ex-

  emitter cimer, the excimer is formed by the following reaction sequence: e + Xe Xe * (3 P 2) + e Xe + C 12 + Xe C 11 + Cl X-Cl + Xe + M + Xe 2 cl + M Xe 2 Cl 'V 2 Xe + Cl + hpv 450-550: *, 4

  wherein M is Ne or any other suitable buffer gas.

  It has been found that over a wide range of discharge conditions such as those of display devices

  typical optics, the precursor molecule Xe C 11 is

  with a high efficiency (in the range of ten to thirty percent), with the highest efficiency for an average

  Approximately four electron volts have been found

  the formation yield of triatomic excimer Xe 2 Cl

  ft is high enough, so that

  parable to that of the prior art for the mixtures Pen-

  ning containing 'can be reached at pressures k

  of the order of atmospheric pressure.

  A mixture of exeimers is tested in an apparatus shown partially in the form of an exploded view in FIG. 1, in which glass plates 110 and 112

  support the X and Y electrodes 123 and 121, whose

  tersections locate the electrical discharges emitting

  light The electrodes are isolated from the

  Gaseous mixture by electrical fibers 130 and 132, formed illustratively by a 0 025 mm glass dielectric coated with a 2 oo nanometers magnesium dioxide electrons layer.

  two dielectric sheets are separated from 0 1 milli-

  meter by a space shutter 140 and the gas 150 occu-

  eg the space between them

  trable, with a duration of 250 nanoseconds and a speed

  se-repeat of 100 kilohertz were applied to

  exposed ends of the electrodes 121 and 123

  capacitive geometry through glass and lox-coatings

  de-magnumsium produced waste within the

gas where the electrodes are crossed.

  The 4 th emission was observed using an OIE filter photometer, the response of which approaches the response of the human eye in order to measure relative brightness as a function of pressure and tension. The

  The emission spectrum of the discharge was analyzed using

  A gaseous monochrometer with a response of a S-5 rhotomultiplier. The illustrative gas mixture nominally comprising 2 μ of xenon, 1; chlorine,

  the remaining neon, gave the test results mon-

  very in Figures 2 and 3. Figure 2 illustrates the measured spectral signal

  excimer mixture at two different pressures.

  Figure 2A illustrates the signal at a pressure of 0 100 tar, showing the characteristics of peak 212 of Xe Cl '

  and the peak 214 of the strongest transition in the

  sitle in the neon-xenon Penning mix, but pre-

  feeling only a very weak intensity in the

  figure 216 characteristic at Xe 2 Cl Figure 2 B illus-

  the signal of the same mixture at a pressure of 0 667 bar, having in addition to the peak 222 of Xe Cl and the peak 224 of the neon, a peak 226 of Xe 2 Cl * dominating the exit

  It should be noted that the species exci-

  mother is excited with such a great output that the neon line 224 is relatively insignificant Indeed, the characteristic color of the neon is not visible

for the naked eye.

  Fig. 3A illustrates the variation of pulse amplitude with pressure in the embodiment of Fig. 1, which produces a discharge having a width

  about one millimeter and Figure 3 shows the

  Relative launches of two gaseous media, the gaseous mixture of excimers and the neon-xenon Penning mixture of art

  The discharge was observed through a

  be CI; and the units are arbitrary We can see that

  the amplitude of the pulse is substantially similar

  re for both gas mixtures, so that the mixture

  Illustrative excimer can be used with food

  conventional energy supplies appropriate to the

  In FIG. 3B, the exemplary excimer mixture d 4 shines in the light of the prior art optical display and under similar operating conditions.

251668 1

I

  Penning mixture has a pressure; Above 267 Dar.

  I suppose that the anger cries out to continue rising after C, 667 tar, as difficulties may arise.

  I by maintaining the width of the discharge at less than

  high pressure meter - for applications that do not

  Ij not requiring a discharge width less than 1 mi

  limeter, the preferred embodiment may have a pressure

greater than 0.667 bar.

  Figure 4 illustrates another achievement of the in-

  | 1 N, wherein a seven-segment character display tube 400 is shown in Figure 4A, with a semitransparent anode 402 through which the seven

  The cathode segments 404 are visible. FIG.

  Ij feel the viewing tube seen from the side, the inside of the wood

  gastight tier 410 being filled with the

  j 4 zeux of excimer 420 and containing the cathodes 404, whose

  Ij the threads enter the box 410 through the passa-

  The cathodes are controlled by logic circuitry for conventional IS 2 C -on displays illustrated, providing the voltage pulses of FIGS.

t 4 excitation: necessary.

  The gas mixture may be any mixture of

  acting under the influence of an electric discharge to form an excimer emitting radiation in a range

  desired spectral In addition to Xe 2 Cl, excimeres ad & -

  jquats emitting in the visible region are Xe O, Kr O,

  Ar C, Xe 2 Pr and Xe F Other excimers emitting radia-

  In the ultraviolet range and thus can be used with a phosphor are Ar 2, Kr 2, Xe 2, Ar F, Kr F, Xe F, Ar Cl, Kr Cl and Xe Cl. high for the production of a radiation i 4 are protably combinations of at least one atom of an element of the column zero of the periodic table (such

  argon, krypton and xenon) and at least one ato-

  of an element of the seventh column (such as chlo-

re or fluorine).

  The role of neon in the reections of the realization

  illustrated: - should have been replaced by any other tamper

  Adequate data The role of de c 1 was also filled by com dosages containing chl, re such as: HCI, CC or

  Hydrocarbons, which are known to dissolve under the influence

  In the case of Ilexcimer

  Xe F, the fluorine donor may be F 2 or F F 3 Any other

  electrical discharge such as alternating currents

  tif, continuous or Mi can be used.

  1/1) CATEGORY CATEGORY CATEGORY CATEGORY ASSEMBLY INCLUDING: A gastight enclosure, a portion of which is optically transmittable in the visible region of the earth;

  electromagnetic spectrum, so that the

  The optical display may be transmitted from said device; a predetermined gaseous mixture comprising at least one gas contained in said gas-tight enclosure; and several electrodes arranged in such a way

  I O 10 a part of the radiation produced inside the

  said gastight enclosure responsive to a discharge

  passing between at least two of said electro-

  crosses said optically transmissible portion of the

  said gastight enclosure; characterized by -

  a way to pass an electric discharge

  that between at least two of said electrodes of such

  that the atoms of at least one kind of gas react

  under the influence of the said electric discharge for

  form excimeres that emit electro-

  magnetic after dissociative deexcitation.

  2 Optical display device according to the

  1, characterized in that said excimeres

  Emit optical radiation in the visual

corn.

  3 Optical display device according to the

  1, characterized in that said excim 4 res emit an intermediate radiation in the ultraviolet

  of the electromagnetic spectrum and said display device

  further comprising a phosphorus compound to abbreviate

  sorber a portion of said intermediate radiation and

  radiating an optical display in the

  visible of the electromagnetic spectrum.

  4 Optical display device according to one

  any of claims 2 or 3, characterized in that

  at least one gas reacts to form excimers

  taking at least one atom of an element from the column zfr of the table: periodic and with micins an atom of a

  Set the setting of the column of the periodic table.

  Di-so 0, itif optical display according to the re-

  claim 4, characterized in that said exciter makes cranion of the rim produced by Xe ni, Xecl and Xe Ff.

  cuelcrriali dps claims 2 or 3, characterized in that

  3 ee the molecules of said excimer comprise at least one

  atom of an element of the zero column of the periodic table

  at least an oxygen atom.

  7 Disoositive optical display according to one

  any of claims 2 or 3, characterized in that

  that at least one of these different electrodes is

  uosée within said gas-tight enclosure.