FR2725549A1 - ANALOG INDICATOR WITH SELF-LUMINESCENT HAND - Google Patents

Abstract

A self-luminous indicator which can be used in a tachometer, etc., for a motor vehicle comprises an indicator needle (1), a luminescent element (13) and a semi-transparent element (15a). The needle has a housing and a cover (15). In the housing a groove (11B) is formed. The luminescent element is arranged in the groove. The semi-transparent element is arranged in the cover of the needle to diffuse the light emitted by the luminescent element to make it exit from the needle. The groove of the housing has an upper opening whose width is greater than or equal to that of the bottom. The semi-transparent element has an upper wall whose width is greater than or equal to that of its bottom. With this arrangement, the needle projects light having a uniform and high brightness towards an observer without it being subjected to a total reflection in the semi-transparent material in order to improve the visibility of the deflection of the needle on a dial.

Description

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  The present invention relates to an improved analog indicator which can be used in a tachometer, etc., for a motor vehicle. More particularly, it relates to an analog indicator of simple realization, whose indications

are very precise.

  Japanese patent publication No. 4-204323 of the applicant describes a self-luminescent indicator for a gauge which can be used with an automobile tachometer. This conventional indicator includes a needle in which are placed light-emitting diodes which emit light via a lens in order to improve the

  visibility of the needle deflection on a dial.

  The lens is mounted in the needle along its length, and has a trapezoidal shape in which the width of the upper surface is smaller than that of the lower surface. Thus, the light emitted by the diodes reaches the upper surface of the lens at a greater angle of incidence, whence the total reflection of the light. More specifically, most of the light reflected by the lateral surface of the lens is not projected outside of the latter, so that the brightness of the light emitted by the diodes decreases

when it comes out of the needle.

  Consequently, the object of the present invention is to avoid the drawbacks of the prior art. Another object of the present invention is to provide an analog indicator comprising a needle designed to direct the light emitted by light-emitting diodes arranged in its interior towards an observer so as to give a high brightness, representative of the deflection of the needle on a dial. According to one aspect of the present invention, there is provided an auto-luminescent indicator which includes a

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  needle of given length, said needle comprising a housing and a cover for covering the housing, a groove made in the housing along the given length of the needle, a luminescent element disposed in the groove, and a semi-transparent element located at inside the needle cover for dispersing the light emitted by the luminescent element outside the needle, this element comprising side walls which extend along the length of the needle, a lower wall facing the luminescent element,

  and an upper wall opposite the lower wall.

  The groove has a bottom on which the luminescent element is disposed and an upper opening from which the light emitted by the luminescent element exits. The width of the upper opening is greater than or equal to that of the bottom. The width of the upper wall of the semi-transparent element is greater than or equal to

that of the lower wall.

  In the preferred embodiment of the invention, a lens is further provided which is interposed between the needle cover and the luminescent element located inside the groove in order to direct the light emitted by the element. luminescent towards the semi-transparent element. The width of the bottom of the groove is less than or equal to that of the wall

  bottom of the semi-transparent element.

  The lens has a lower surface facing the luminescent element and a wavy upper surface. The corrugated upper surface has a multitude of projections similar to triangular poles which are opposite the needle cover. The lens is partially protruding on

  the groove in the direction of the needle cover.

  In the cover, a groove is formed at

  the interior of which is arranged the trans-

  parent. The lens is partially inserted into the

cover groove.

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  The side walls of the semi-element

  transparent are substantially flat.

  The width of the upper wall of the semi-transparent element is substantially identical to that of the lower wall. The side walls of the semi-transparent element are oriented parallel to the axis of the housing, which extends perpendicular to the bottom of the groove on which the luminescent element is arranged. The width of the upper opening of the groove is substantially equal to that of the bottom. The groove has side walls which extend

parallel to each other.

  The luminescent element comprises a multitude of electroluminescent elements arranged in a

given length of the groove.

  A transparent resin element is also arranged inside the groove in which

is the luminescent element.

  According to another aspect of the present invention, there is provided a self-luminescent indicator which comprises an indicator needle having a given length, the needle comprising a housing and a cover for covering the housing, a first groove made in the housing along the length given by the needle, a second groove made in the housing along the given length of the needle, the second groove communicating with the bottom of the first groove, a luminescent element disposed on the bottom of the second groove, a lens disposed at the interior of the first groove, having a first surface in

  which enters the light emitted by the lumines element-

  hundred and a second surface from which the light entering the first surface comes out, the second surface being wavy, a semi-transparent element disposed inside the needle cover in order to scatter the light coming from the lens and leaving of the needle, the semi-transparent element comprising

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  side walls which extend along the length of the needle, a lower wall facing the luminescent element, and an upper wall opposite the lower wall. The second groove has an upper opening opposite its bottom. The width of the upper opening is greater than or equal to that of the bottom. The

  width of the upper wall of the semi-element

  transparent is greater than or equal to that of the lower wall. In the preferred embodiment of

  the invention, the side walls of the semi-element

  transparent are substantially flat.

  The width of the upper wall of the semi-transparent element is substantially identical to that of the lower wall. The side walls of the semi-transparent element are oriented parallel to the axis of the housing, which extends perpendicular to the bottom of the second groove on which is disposed

the luminescent element.

  The second groove has a pair of flat side walls and an opening whose width is substantially identical to that of the bottom wall of the semi-transparent element. The second groove has a pair of flat side walls and an opening whose width is greater than or equal to

  that of the bottom of the second groove.

  The bottom of the first groove limits the vertical movement of the lens, while the side walls of the first groove limit the

  lateral displacement of the lens.

  The luminescent element comprises a multitude of electroluminescent elements arranged in a

  given length of the second groove.

  The indicator needle cover is made of a non-transparent material. The needle housing is also made of a non-transparent material.

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  The present invention will be well understood

  during the following description made in connection with

  the accompanying drawings in which: Figure 1 is a partial sectional view of a self-luminescent indicator according to the present invention; Figure 2 is an exploded perspective view showing the auto-luminescent indicator of Figure 1; Figure 3 is a perspective view of flexible printed circuits 12 and 5; Figure 4 is a sectional view of an indicator needle according to the first embodiment of the invention; FIG. 5 is a circuit diagram which represents a conductive pattern of the flexible printed circuit 12 on which light-emitting diodes are mounted; FIG. 6 is a sectional view of the optical paths of the lights reflected by a lens 14,

  which are emitted by the electro-diodes

  luminescent mounted on the flexible printed circuit 12; Figure 7 is a sectional view of a second embodiment of an indicator needle; Figure 8 is a sectional view of a third embodiment of an indicator needle; Figure 9 is a sectional view of a fourth embodiment of an indicator needle; and Figure 10 is a sectional view of a fifth embodiment of an indicator needle. In Figure 1, there is shown an analog self-luminescent indicator according to the present invention, which can be used in a tachometer for vehicle

automotive, for example.

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  The self-luminescent analog indicator comprises a needle drive assembly 2 fixed to the indicator housing (not shown), a needle support shaft 3 which extends upwards from the unit needle drive, a self-luminescent indicator needle 1, supported on the upper end of the shaft 3, a flexible printed circuit 5 (hereinafter referred to as CIF), and a plate character display 4 (i.e. a dial) on which notches are printed. The CIF comprises, as shown in Figures 2 and 3, a strip plate which is wound around the outer surface of the shaft 3 of the needle holder, and this several times, in a plane in the manner of a spiral and which communicates electrically with

  self-luminous elements such as light-emitting diodes

  luminescent arranged inside the needle 1.

  The needle drive unit 2 is of the crossed coil type which responds to an input signal representative of an indicator parameter such as the speed of the engine or of the vehicle to supply a torque to the shaft 3 of the needle holder. A balance spring 6 is fixed at its end to the shaft 3 to provide a reaction force against the torque produced by the coil so that the needle 3 is maintained in the position o the torque due to the coil and the forces CIF 5 and spring 6 elastics are balanced. The needle 1, as shown in FIGS. 2 to 6, comprises a housing 11, a flexible printed circuit (CIF) 12 disposed in the housing 11 extending in the longitudinal direction, a multitude of light-emitting diodes 13, a transparent element 16 made of synthetic resin placed on the CIF 12, a dioptric lens 14 placed on the element 16,

  and a cover 15 placed on the housing 11.

  The housing 11 is made of a non-transparent synthetic resin and comprises, as

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  shown in Figure 4, a square rod member having internally a first groove 11A which extends in the longitudinal direction and a second groove 11B formed in the bottom of the first groove 11A, having an opening whose width Li is narrower than the width L4 of the opening of the first groove 11A. The second groove 11B is defined by lateral walls 11b extending parallel to each other over the length of the needle 1 which are substantially perpendicular to the upper surface of the housing 11. The bottom of the second groove 11B has therefore the width L1. The light-emitting diodes 13 are

  arranged on the bottom of the second groove 11B.

  The housing 11 also comprises, as is clearly shown in FIG. 2, a boss 11a formed in one piece on the end portion of the rod element, projecting downwards from it. A bore 11f is formed in the lower part of the boss 11a into which the needle support shaft 3 is inserted so as to rotationally support the needle 1. The CIF 12 is disposed on the bottom of the second groove 11B of the housing 11, and may be provided in a manner in which an insert (i.e., the CIF 12) is disposed within a

  mold during the formation of the housing 11.

  The cover 15 is made of black synthetic resin and comprises, as shown in FIG. 2, in

  a longitudinally central part, a semi-portion

  transparent in strip 15a consisting of a trans-

  parent that has a light scattering characteristic. On the two longitudinal edges of the cover 15, hook portions 15d are formed which project inwardly for firm engagement with shoulder portions llg, as is

  shown in FIG. 2, of the housing 11.

  The portion 15a is arranged so as to be opposite the light-emitting diodes 13 of the CIF 12,

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  and has an upper surface 15d, flat side surfaces 15b, and a lower surface 15c. The upper surface 15d has the width L1. The lateral surfaces 15b extend substantially by being parallel to each other and perpendicular to the upper surface of the housing 11 (that is to say the axis C of the housing which extends perpendicular to the bottom of the second groove 11B). More specifically, the semi-transparent strip portion 15a is substantially rectangular in terms of cross section so as to have the width L1 of the lower surface 15c

  which is equal to the width L1 of the second groove 11B.

  In forming the cover 15, the portion 15a can first be formed by pattern stretch molding and then be inserted into shaping dies. However, it is difficult to remove the portion 15a from the dies unless the lateral surfaces 15b are chamfered, which can cause the edges of this portion 15a to be deformed. Therefore, it is desirable that the side surfaces 15b of the portion 15a are parallel to each other; however, they can be inclined in a given angular range which has no effect on the characteristics of an optical system incorporating the semi-transparent portion 15a. When using the

  portion 15a having the lateral surfaces 15b changed

  braked, it is desirable that a narrow width portion is oriented towards the lower end of the

cover 15.

  Similarly, the side walls llb of the second groove 11B can be chamfered according to a given angular range in order to facilitate

  their removal from the shaping dies.

  The CIF 12 disposed in the housing 11 has on its top a conductive pattern, on which are mounted the light emitting diodes 13 at regular intervals. The diodes 13, as shown in Figure 4, are provided in the element 16 in resin s-rthéticue tra-.sarente enda.nt the molding of this element. In addition,! E CF 12 is, cor = e represented in FIG. 3, form., É e. used with the C-F in siral 5 via a CIF of liaiscn 12a which extends: parallel to the bossaze lia. CiF 5, 12 e_ 1] a peuven: re f ormrs en followzan a manner dans l'elle _n moif condu uc: eur in copper film es: for-. on the surface of a base film of resin this poymid, and an insulating film. is then applied to an area of the conductive pattern other than the terminals which are

  in contact with terminals 3a and 9b fixed on a terminal connector 8.

  As shown in figure -, on the moti_ driver of the CIF 12, a multu of the e-rae -ged, cnacune comprising diodes m13 dis. dares in series, are mounted in parallel to regular te .-- alles between positive and negative conductive wires Sa and 5b which are impr-m..és on the surface of C-iF 12, of CIF of connection 12a and CF in propeller 5 in the

direction of their reader.

  The! Enti! E 14 mounted in the first groove !! A formed in the transparent synthetic resin element 16 comprises, co = e rerésen.é ren fgure5, a bar element having on its top a corrugated surface 14a in the present angles of the upper ends and of the bottoms of the surface 14a represent degrees, resdectiverer., so that the lights emitted by the diodes 13 are projected with a

  uniform shine by the proportion of semi-stripes

  transparent! Its 'needle' in the longitudinal direction. R-Jangular ples (ie undulations) forming the surface 4a of the lens 1 are arranged in parallel in the direction of the arc of the lens. The surfaces of each of the poles are flat as is clearly shown in the drawing, however, they can be curved. The lens 14, as we have ex: Dlicu above, is arranged inside the first rai-nure 1A of the housing 11, of so cue its eplacen ... ver - cal est

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  limited by the bottoms lld (that is to say, by the shoulder parts continuing the side walls llb of the second groove llB) of the first groove 11A and its lateral displacement is limited by the side walls of the first groove 11A. In operation, when the crossed coil of the needle drive unit 2 is activated in accordance with an input signal representative of an indication parameter, it will cause the needle 1 to rotate while the CIF 5 fixed between a rotating element (that is to say the indicator needle) and a stationary element (that is to say the connecting disc 8 of unit 2), is deformed, or has bent and is maintained in a place in which the engine torque of unit 2 is balanced by the reaction torques produced by the CIF 5 and the spring 6 of unit 2 to be directed to a value of an indication parameter of the display plate 4. In this arrangement, the Young's module of the CIF 5 is much smaller than that of the spring 6 and consequently the needle 1 can be rotated by a torque similar to that of a conventional type. without having any effect

  on the precision of the indication of needle 1.

  The light-emitting diodes 13 respond to a lighting current supplied from the lighting circuit (not shown) via the spiral CIF 5, and the connecting CIFs 12a and 12, so as to be switched on and to produce a light which is dispersed from the semi-transparent strip portion 15a of the cover 15 in the direction of the observer of the indicator and that of the

next way.

  The light beams projected by the diodes 13 disposed on the CIF 12, as shown in FIG. 6, first enter the element 16 made of transparent synthetic resin covering the CIF 12 according to different angles of incidence. The light beams of the diodes 13 emitted laterally are reflected

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  by the side walls llb of the second groove 11B, so that most of them enter the lens 14. The light beams entering the lens 14 are dispersed by the corrugated surface 14a in the longitudinal direction of the needle 1, and enter then in the semi-transparent strip portion 15a of the cover 15 so that they are projected from the upper surface 15d of the portion 15a to exit the needle 1. The light beams entering the portion 15a are partially reflected by the side surfaces 15b extending vertically, so that the reflected light beams enter the upper surface 15d at a small incident angle. As a result of the vertical orientation of the side surfaces 15b, this incident angle is less than the critical angle at which the total reflection occurs inside the portion 15a, so that the light beams reflected by the side surfaces b are projected out of the portion 15a, which ensures the visibility of the deflection of the needle on the dial 4. In addition, as the lateral surfaces 15b of the portion 15a extend parallel to each other and perpendicular to the housing 11, the light beams coming from the diodes 13 sufficiently reach the angles of the portion 15a, that is to say the edge portions of the upper surface 15c continuing the side surfaces 15b. This is due to the fact that the width of the upper surface 15d (and of the lower surface 15d) is, as indicated above, equal to the width L1 of the opening of the second groove 11B, so that the light beams leaving the second groove 11B are directed towards the upper surface 15d, then are projected uniformly in terms of gloss over a preselected length of the portion 15a without being dispersed in the direction of the width of this portion. In connection with FIG. 7, a second embodiment of the present invention is shown,

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  which is different from the above structure of the needle with regard to the shape of the element 16

  in transparent synthetic resin. The other agencies-

  are identical to those of the first embodiment and their detailed explanation will be omitted.

  Element 16 made of transparent synthetic resin

  Parent, as can be seen in the drawing, has a trapezoid-shaped cross section, having chamfered side surfaces which are formed symmetrically. Similarly, the groove 11B formed in the housing 11 has chamfered side walls 11b which are oriented upwards at a given angle so that the upper width Li of the groove 11B is greater than its lower width L2. In other words, the surface of the end of the upper opening of the groove 11B is greater than that of the bottom. As in the case

  shown in Figure 4, the semi-strip portion

  transparent 15a of the cover 15 has the same width L1

on its height.

  In operation, certain light beams emitted by the light-emitting diodes 13 propagate laterally so that they reach the side walls llb of the groove 11B. The light beams having reached the side walls llb are all reflected upwards, without remaining in the element 16 of transparent synthetic resin and are then transmitted by the lens 14 and the portion 15a to exit the needle 1 with high efficiency , from where

  improving the brightness of needle 1.

  FIG. 8 represents a third embodiment of the needle 1 which is different from the second embodiment in that the portion of semi-transparent strip 15a has chamfered lateral surfaces 15b which are oriented upwards symmetrically by relative to the given optical path of the diodes 13 so that the upper width L3 is greater than the lower width L1 equal to the width

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  element 16 of transparent synthetic resin. Similarly, the groove 70 of the

  cover 15 has changeable side surfaces

  braked 40a which are in contact with the lateral surfaces 15b of the portion of semi-transparent strip

parent 15a.

  In operation, the light beams which have reached the lateral surfaces 15b of the portion of semi-transparent strip 15a after having passed through the element 16 of transparent synthetic resin and the lens 14, are reflected upwards. These reflected beams reach the upper surface 15d at an incident angle less than the critical angle so that they are all projected outside the needle 1. It will be noted that the lateral surfaces 15b, oriented upwards, of the portion 15a allow all incoming light beams to be directed outside of

needle 1.

  FIG. 9 represents a fourth mode of

  production of the indicator needle 1.

  In the cover 15 is formed a groove having a width L1. In the housing 11 is also formed a groove 11C having the same width L1. The grooves 70 and 11C are arranged in vertical alignment with each other. In addition, the semi-transparent strip portion 15a, the transparent synthetic resin element 16, and the lens 14 have the same width L1. The portion 15a is mounted in the groove 70 so that it is flush with the upper surface of the cover 15 to form a hollowed-out lower part 80 which serves to precisely position the cover 15 during assembly of the needle 1, then that the transparent synthetic resin element 16 is disposed entirely in the groove 11C. The lens 14 is partially inserted into the hollowed-out lower part 80 which is formed in the groove 70, while the rest is mounted in the groove 11C. As clearly shown in the

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  Drawing, the portion of semi-transparent strip 15a has a substantially rectangular configuration in cross section. In a similar manner to the first variant, the side walls 15b and 11b extend parallel to the given optical path of the light-emitting diodes 13 (that is to say the vertical axis C

housing 11).

  With the previous arrangements, all

  light beams radiated by electro-diodes

  luminescent 13 are effectively projected from the portion of semi-transparent strip 15a without being

left in the lens 14.

  FIG. 10 represents a fifth mode of

  production of the indicator needle 1.

  In the cover 15 is formed a chamfered groove 71 having inclined side walls 40a which are oriented upwards. Similarly, in the housing 11 is also formed a chamfered groove 11C having inclined side walls 11b which are oriented upwards, continuing the side walls 40a. The semi-transparent strip portion 15a has chamfered side surfaces 15b which are mounted in the groove 71 so as to be partially projecting in the direction of the bottom. Similarly, the element 16 made of transparent synthetic resin also has chamfered side walls with a contour similar to that of the side walls llb of the groove 11C, and is mounted in the groove 11C so as to form a recessed part 80 on its upper surface with which the projecting part of the transparent strip portion 15a is in contact to facilitate the installation of the cover 15 during assembly of the needle 1. The needle 1 of this embodiment, as appears in the drawing, do not use the lens 14. The lens 14 can not be used as long as it is not necessary to have a uniform dispersion of the light according to the

length of the needle.

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  When using the lens 14, it is desirable that its corrugated surface 14a is disposed completely inside the groove 11C to form a recessed portion for engagement with the projecting portion of the portion of semi-transparent strip 15a to facilitate the installation of the cover 15 on the

  housing 11 during assembly of needle 1.

  In addition, the inclined angle of the side walls 40a of the groove 71 may be different from that of the side walls 11b of the groove 11C. In this case, the width of the interior surface of the portion of semi-transparent strip 15a is preferably made equal to that of the upper opening of the groove 11C in order to direct all the light beams.

  emitted by the diodes 13 in the portion 15a.

  In addition, while in the previous embodiments, the side walls of the portion 15a are flat, they can alternatively be provided with fine projections. This arrangement also directs the light reflected on the side walls of the portion a in the upward direction so that it is projected out of the needle 1 with great efficiency. Similarly, fine projections can be formed on the side walls 40a and llb

grooves 70 and 11B (11C).

  Furthermore, the lens 14 can be omitted in the first and second embodiments. In this case, practically the same effects are obtained although the dispersion of the light in the direction of the length of the needle 1 is substantially degraded. In addition, a chamber can be formed in the bottom of the cover to receive the lens 14 without having to form the lens receiving groove (11A or 11C).

in housing 11.

  The present invention is not limited to the examples which have just been described, it is on the contrary liable to modifications and variants

  which will appear to those skilled in the art.

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Claims (16)

  1 - Self-luminescent indicator, characterized in that it comprises: - an indicator needle (1) having a   given length, this needle comprising a pocket   ment (11) and a cover (15) for covering the housing; - A groove (11A) formed in the housing along the given length of the needle; a luminescent element (13) disposed in the groove; and - a semi-transparent element (15a) disposed inside the cover of the needle in order to scatter the light emitted by the luminescent element   to get it out of the needle, this semi-element   transparent comprising lateral walls (15b) which extend along the length of the needle, a lower wall (15c) facing the luminescent element, and an upper wall (15d) opposite the lower wall, in which the groove has a bottom on which the luminescent element is disposed and an upper opening from which the light emitted by the luminescent element exits, the width of the upper opening being greater than or equal to that of the bottom, and in that the width of the upper wall of the semi-transparent element is greater than or equal to that of the bottom wall.   2 - Indicator according to claim 1, characterized in that it further comprises a lens (14) interposed between the cover (15) of the needle (1) and the luminescent element (13) inside the groove to direct the light emitted by the luminescent element towards the semi-transparent element (15a), and in that the width of the bottom of the groove is less than or equal to that of the bottom wall of the semi-transparent element transparent. 3 - Indicator according to claim 1 or 2, characterized in that the lens (14) has a lower surface facing the luminescent element   (13) and a corrugated upper surface (14a).   4 - Indicator according to claim 3, characterized in that the undulating upper surface (14a) of the lens comprises a multitude of projections similar to triangular poles which are opposite of the needle cover.   5 - Indicator according to claim 2, characterized in that the lens (14) is partially projecting from the groove (11A) in the direction of needle cover (15).   6 - Indicator according to claim 5, characterized in that on the cover (15) is formed a groove inside which is arranged the semi-transparent element, the lens being inserted   partially in the groove of the cover.   7 - Indicator according to any one of   previous claims, characterized in that the   side walls (15b) of the semi-transparent element (15a) are substantially flat.   8 - Indicator according to any one of   previous claims, characterized in that the   width of the upper wall (15d) of the semi-element   transparent (15a) is substantially identical to that of the lower wall (15c), and in that the side walls of the semitransparent element are oriented parallel to the axis (c) of the housing (11) which extends perpendicular to the bottom of the groove on which is arranged the luminescent element.   9 - Indicator according to any one of   previous claims, characterized in that the   width of the upper opening of the groove is   substantially equal to that of the bottom.   - Indicator according to any one of   previous claims, characterized in that the 18 2725549   groove has side walls that extend parallel to each other.   11 - Indicator according to any one of   previous claims, characterized in that   the luminescent element comprises a multitude of electroluminescent elements (13) arranged along a length given in the groove.   12 - Indicator according to any one of   previous claims, characterized in that   further comprises a transparent resin element (16) disposed inside the groove, this element being   placed in the luminescent element.   13 - Self-luminescent indicator, characteristic   se in that it comprises: - an indicator needle (1) having a given length, the needle comprising a housing (11) and a cover (15) for covering the housing; - a first groove (11A) formed in the housing along the given length of the needle; - a second groove (11B) formed in the housing along the given length of the needle, the second groove communicating with the bottom of the first groove; - a luminescent element (13) disposed on the bottom of the second groove; - a lens (14) placed inside the first groove, having a first surface in which enters the light emitted by the luminescent element and a second surface from which the light entering the first surface exits, the second surface (14a) being wavy; - a semi-transparent element (15a) disposed in the cover of the needle for dispersing the light coming from the lens and for making it exit from the needle, this semi-transparent element having side walls (15b) which are extend along the length of the needle, a lower wall (15c) in 19 2725549   look of the luminescent element, and an upper wall (15d) opposite the lower wall, in which the second groove has an upper opening opposite its bottom, the width of the upper opening being greater than or equal to that of the bottom , and in which the width of the upper wall of the semi-transparent element is greater   or equal to that of the bottom wall.   14 - Indicator according to claim 13, characterized in that the side walls of the element   semi-transparent (15a) are substantially flat.   - Indicator according to claim 13, characterized in that the width of the upper wall of the semi-transparent element is substantially identical to that of the lower wall, and in that the side walls of the semi-transparent element are oriented parallel to the axis (c) of the housing, which extends perpendicular to the bottom of the second groove on   which is arranged the luminescent element (13).   16 - Indicator according to any one of   claims 13 to 15, characterized in that the second   groove (11B) has a pair of flat side walls and an opening whose width is substantially   equal to that of the bottom wall of the semi-element transparent.   17 - Indicator according to any one of   claims 13 to 16, characterized in that the second   groove (11B) has a pair of flat side walls and a wider opening   or equal to that of the bottom of the second groove.   18 - Indicator according to any one of   claims 13 to 17, wherein the bottom of the   first groove (11A) limits the vertical movement of the lens (14), while the side walls of the first groove limit the lateral movement of the lens. 19 - Indicator according to any one of   claims 13 to 18, characterized in that the element 2725549   luminescent includes a multitude of electro-   luminescent (13) arranged along a given length of the second groove (11B).   - Indicator according to any one of   previous claims, characterized in that the   cover (15) of the indicator needle (1) is in non-transparent material.   21 - Indicator according to any one of   previous claims, characterized in that the   housing (11) of the needle (1) is made of non-transparent material.