JP2009265960A - Traffic signal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a traffic signal and a railway signal of low electric power consumption and high brightness, by distributing light from the traffic signal only in a necessary direction so as to utilize the light. <P>SOLUTION: The traffic signal of high directivity is provided using a laser beam, and desired light distribution is attained by revising a shape of a deflection groove of an edge light waveguide panel. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a traffic signal device and a railroad signal device that use laser light as a light source.

  Conventionally, as traffic traffic signals and railway traffic lights, incandescent bulbs are built in a bowl-shaped reflector, and the floodlight cover that closes the projection opening end of the reflector is colored blue, yellow, and red. Has been used. In recent years, along with the increase in luminance of light emitting diodes (hereinafter referred to as LEDs), LEDs having good luminous efficiency and long life have been used as the light sources of these traffic lights.

  In such a traffic signal, particularly in a railway traffic signal, directivity of light emitted from the traffic signal is required. This is because if the light from a traffic light is scattered inside a tunnel or the like, there is a risk that the signal appears to be displayed even outside the target lane.

  In response to such a problem, a traffic signal with a narrow viewing angle has been proposed. For example, in Patent Document 1, a blinker (blindfold) having a small hole diameter is provided in front of an LED light source, and only light emitted to the front is allowed to pass.

  In addition, traffic signals require light distribution directivity of the traffic lights in order to reduce power consumption and to ensure the necessary brightness as seen from the driver of the automobile. However, in traffic signals, it is necessary to distribute light in the downward direction as well as in the front direction, and it is desirable to have a light distribution characteristic that is asymmetrical in the vertical direction when viewed from the traffic signal.

For example, in Patent Document 2, the light source is shifted upward from the focal position of the light projecting optical system and the light source position can be adjusted, and light is emitted slightly downward.
JP 2006-142850 A JP-A-6-349307

  However, in the configuration of Patent Document 1, only the light emitted other than the front is shielded, so the shielded light is not effectively used. In the configuration described in Patent Document 2, the light distribution characteristic in the left-right direction is not described. In other words, if the viewing angle in the left-right direction is narrowed, the problem is that the signal is difficult to see from the side of the road near the traffic light. Conversely, if the viewing angle in the left-right direction is widened, the signal is far away from the road. Because it is illuminated up to a place, the use of light is wasted, and it is annoying for neighboring residents.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and provides a traffic signal and a railroad traffic light having low power consumption and high brightness by distributing light from a traffic light only in a necessary direction and effectively using the light. The purpose is to do.

  In order to achieve the above object, a traffic light of the present invention includes a light source that emits laser light, a surface light emitting unit that spreads and emits light emitted from the light source, and light emitted from the light source. And an optical fiber guided to the light source, and a signal control unit that controls light emission and extinction of the light source.

  With this configuration, a traffic light with high directivity, high luminance, and low power consumption can be realized. Further, since the light source can be disposed at a position away from the light emitting unit, maintenance such as replacement of the light source is easy.

  At this time, the surface light emitting unit includes a linear light guide unit that linearly spreads the laser beam emitted from the optical fiber and emits the laser beam emitted from the linear light guide unit from the side surface, and one main surface. And the linear light guide unit is configured to emit substantially parallel light, and the light guide plate transmits incident light to the opposing surface of the one main surface. There is a deflection groove that deflects toward the main surface, and the deflection groove is formed in parallel to the incident surface on which light is incident. With this configuration, high directivity can be obtained, and it is useful as a railway traffic signal that prevents misunderstandings in tunnels and the like.

  Alternatively, the surface light emitting unit includes a ring-shaped light guide unit that converts the laser light emitted from the optical fiber into a ring-shaped light beam, and one main surface that causes the laser light emitted from the ring-shaped light guide unit to be incident from the outer peripheral side surface. The ring-shaped light guide unit is configured to emit light from the inner peripheral side surface toward the center. Even if comprised in this way, high directivity is obtained and it is useful as a railway traffic signal.

  Further, the surface light emitting unit includes a cylindrical lens array adjacent to the one main surface of the light guide plate, and is configured to diffuse light emitted from the light guide plate in the one-dimensional direction by the cylindrical lens array. If comprised in this way, it can be used as a traffic signal.

  Alternatively, the deflection groove of the light guide plate is configured such that the deflection surface is formed as a curved surface, and the inclination angle of the deflection surface with respect to the one main surface gradually changes between 0 degrees and 45 degrees. Even if comprised in this way, it can be used as a traffic signal.

  Alternatively, the deflection groove of the light guide plate is composed of various types of deflection grooves having different inclination angles with respect to the one main surface of the deflection surface, and the deflection surface of each deflection groove has an inclination angle with respect to the one main surface of 0 degree. Between 45 degrees. Even if comprised in this way, it can be used as a traffic signal.

  Furthermore, the deflection surface of the deflection groove has a diffusion groove for diffusing light in a direction orthogonal to the direction in which the deflection surface has a curvature, and the diffusion groove has an inclination angle with respect to the one main surface of the deflection surface. The smaller the size, the wider the diffusion. With this configuration, when used as a traffic signal, the signal light can be distributed only to the area along the road, so that the light emitted from the signal can be used effectively, and the signal device has a high luminance and low power consumption. Can be realized.

  Alternatively, the deflection surface of the deflection groove has a curvature in a direction orthogonal to the direction in which the deflection surface is inclined with respect to the one emission surface, and is wider as the inclination angle of the deflection surface with respect to the one main surface is smaller. Configure to spread. Even when configured in this way, when used as a traffic signal, the signal light can be distributed only to the area along the road, so that the light emitted from the signal can be used effectively, and further, with high brightness and low power consumption Can be realized.

  In addition, at least two laser light sources that emit laser light of the same wavelength, a signal control unit that independently controls light emission and extinction of the at least two laser light sources, and laser light emitted from the at least two laser light sources, respectively A surface light emitting portion that is incident and spread out in a plane, and the laser light emitted from the at least two laser light sources is emitted from the surface light emitting portion with directivity at different angles. Configure. If comprised in this way, when using as a traffic signal, a signal can be displayed independently according to the distance of a signal and a vehicle, and the safety or smoothness of traffic can be improved.

  At this time, the light guide plate is configured such that laser light is incident from the side surfaces on both sides, and the deflection groove of the light guide plate has two deflection surfaces that deflect at different angles depending on the direction in which the light enters. Configure as follows. If comprised in this way, the signal apparatus which can display a signal independently in a different different direction is realizable.

  Further, the emitted light is configured to be linearly polarized light or circularly polarized light. If comprised in this way, if a driver | operator uses a polarizing filter together, the influence of the sun can be reduced and the visibility of a traffic light can be improved.

  Further, the surface light emitting unit has a region where the polarization of the emitted light is orthogonal to the polarization of the light emitted from the other region, and the region is a predetermined symbol corresponding to the color of the light emitted from the surface light emitting unit. It is comprised so that it may become the shape of this. If comprised in this way, if polarization glasses etc. are used, a color blind person will become easy to recognize a signal and can prevent misidentification.

  The surface light emitting unit includes a diverging element that uniformly spreads the laser light emitted from the optical fiber and a collimating element that imparts a predetermined light distribution characteristic to the laser light emitted from the diverging element. If comprised in this way, since high directivity is obtained, it can be used as a railway traffic signal.

  The laser light source includes a laser light source that emits red and green laser light, and is configured to guide the red laser light and the green laser light to a surface light emitting unit for a yellow signal. If comprised in this way, the display which light-emits yellow can be implement | achieved.

  According to the present invention, a traffic light with high brightness and low power consumption can be realized. In addition, since a railway traffic signal with high directivity can be realized, it is possible to reduce the risk of misrecognizing signals other than the intended lane. Furthermore, the use of a polarizing filter also has a great effect as a traffic signal device, such as improving the visibility when the sun is in the background, or preventing misidentification of a signal of a color blind person.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same element and description may be abbreviate | omitted. In addition, the drawings schematically show each component mainly for easy understanding, and the shape and the like are not accurate.

(Embodiment 1)
FIG. 1 shows a schematic configuration of a traffic light 10 according to the present embodiment. FIG. 1A is a schematic configuration diagram, and FIG. 1B is a cross-sectional view viewed from line 1C-1C in FIG.

  As shown in FIGS. 1A and 1B, the traffic light 10 according to the present embodiment includes a light source unit 11 and a signal display unit 12, and light emitted from the light source unit 11 is transmitted to the signal display unit 12 through an optical fiber 13. It is configured to guide. The light source unit 11 includes a laser light source 14, a signal control unit 15 that controls at least light emission / extinction of the laser light source 14, and a condensing lens 17 that guides the laser light 16 emitted from the laser light source 14 to the optical fiber 13. The signal display unit 12 includes a collimating lens 18 that collimates light emitted from the optical fiber 13, a light guide bar 19 that emits light incident from the incident end surface 19a from the side surface 19b, and converts the light into linear light. The light guide plate 20 emits light incident from the incident end surface 20a from one main surface 20b, and the reflection sheet 21 disposed adjacent to the light guide plate 20. Although not shown, the same structure is prepared for each signal color, and is arranged in the same light source unit 11 and the same signal display unit 12. Are connected.

  Here, the laser light source 14 is configured to emit laser light having a wavelength capable of displaying the signal color by the signal color or the additive color of light. Specifically, a red laser light source is used for the red signal, a blue or green laser light source is used for the blue signal, and in the case of the yellow signal, the laser light emitted from the red and green laser light sources is configured to be colored. The

  In addition, a deflection groove 19c configured to totally reflect incident light and deflect it by approximately 90 degrees is provided on a surface opposite to the side surface 19b of the light guide rod 19, and linearly incident light that is incident substantially in parallel is formed. The light is converted into parallel light and emitted. Further, the spacing or depth distribution of the deflection grooves 19c is set so that the light amount distribution of the light emitted from the light guide bar 19 is concentrated near the longitudinal center of the side surface 19b.

  In addition, a polarization groove 20d that reflects incident light totally and deflects it toward one main surface 20b is provided on the opposing surface 20c of the one main surface 20b of the light guide plate 20. The deflecting groove 20d is provided in parallel to the incident end face 20a, and is configured to deflect and emit light that is incident substantially in parallel while being parallel. Further, the deflection groove 20d is formed in a circular region in accordance with the region to emit light.

  The region where the deflection groove 20d is formed may be the entire surface of the opposing surface 20c. In this case, the light emitted from the light guide bar 19 is configured to be uniform.

  In the traffic light 10 configured as described above, the laser light 16 emitted from the laser light source 14 is parallel light to the light guide rod 19 inside the signal display unit 12 via the condenser lens 17, the optical fiber 13, and the collimator lens 18. , Is deflected by the deflection groove 19c, and is emitted as substantially parallel light from the side surface 19b. Similarly, the laser light 16 emitted from the light guide rod 19 enters the light guide plate 20 as substantially parallel light, is deflected by the deflection groove 20c, and is emitted as substantially parallel light from one main surface 20b. The laser light 16 emitted from the light guide plate 20 is substantially parallel light, and is extremely directional light.

  As described above, in this embodiment, a traffic light having a very high directivity can be realized with a simple configuration by using a laser light source. Such a highly directional traffic light, for example when placed inside a tunnel, can reduce the light reflected from the traffic light from being reflected and scattered by the wall surface of the tunnel. It is useful as a traffic light with less danger.

  Further, unlike the method of increasing the directivity by blocking unnecessary light emitted from the traffic light, all the emitted light can be used effectively, so that a traffic light with high luminance or low power consumption can be realized.

  Further, by using a laser light source, light can be efficiently guided using an optical fiber, so that the light source unit 11 can be arranged at a position away from the signal display unit 12. Conventional traffic lights are often installed at high places, and there is a problem that maintenance such as replacement of light sources is not easy, but the traffic lights of the present embodiment are arranged in a place where the light source unit 11 is easy to work, or A configuration such as collecting the light source portions of a plurality of traffic lights in one place is possible, and maintenance is easy.

  In the present embodiment shown in FIG. 1, the laser light 16 emitted from the optical fiber 13 is configured to spread in a planar shape using the light guide rod 19 and the light guide plate 20, but uniformly using the diffusion element. It is good also as a structure which expands a laser beam.

  FIG. 13 shows a configuration using a diffusing element. The laser light 16 emitted from the optical fiber 13 is uniformly spread using the diffusing element 51, folded back by the reflecting plate 52, and converted into substantially parallel light by the Fresnel lens 53. It is configured to do. Even with this configuration, outgoing light with high directivity can be obtained with a simple configuration.

  In the present embodiment, light having a high directivity is emitted in the front direction of the traffic light. However, the deflection surface of the deflection groove 20d of the light guide plate 20 is curved, or a cylindrical lens array is provided on the front surface of the traffic light. By arranging, the light distribution range can be expanded to the range from the front direction to the lower direction, and can be effectively used as a traffic signal.

  FIG. 2 shows an enlarged view of the deflection groove 20d when the deflection surface is curved, and the deflection groove 20d has an inclination angle with respect to one main surface 20b that gradually changes between 0 degree and 45 degrees. It is configured. With this configuration, the light deflected by the deflection groove 20d is emitted in a range between the front direction and the lower direction of the traffic light, and the light is not emitted in unnecessary directions in the upper direction and the left and right directions. High traffic signal can be realized.

  Alternatively, the same effect can be obtained by randomly arranging various types of deflection grooves having different inclination angles with respect to the one main surface 20b of the deflection surface at high density.

  FIG. 3 shows a cross-sectional view of the signal display unit 12 using the cylindrical lens array 22. In this figure, the light guide plate 20 is configured to emit light substantially parallel downward, and is configured to diffuse the light emitted from the light guide plate 20 by the cylindrical lens array 22 in the vertical direction. Even if comprised in this way, since a light is not radiate | emitted to an unnecessary direction of an upward direction and the left-right direction, the traffic signal apparatus with the high utilization efficiency of light is realizable.

  In the present embodiment, the shape of the light guide plate is rectangular, but the shape of the light guide plate may be circular. 4A and 4B are schematic configuration diagrams of a traffic light using a circular light guide plate. FIG. 4A is a schematic configuration diagram, and FIG. 4B is a cross-sectional view taken along line 4C-4C in FIG.

  As shown in FIGS. 4A and 4B, in this embodiment, the light source unit 11 and the optical fiber 13 are the same as those shown in FIG. 1, and the signal display unit 12 includes a ring-shaped light guide 24, The circular light guide plate 25 is provided.

  Here, the ring-shaped light guide 24 is provided on the outer peripheral portion while allowing light to enter from the incident end surface 24 a provided in a part of the ring-shaped light guide and propagating through the inside of the ring-shaped light guide 24. The light is deflected by the polarization groove 24c and emitted toward the center of the ring.

  The circular light guide plate 25 is formed in a conical shape so that light enters from the outer side surface 25a and exits from one main surface 25b. Deflection grooves 25d for deflecting incident light by total reflection are formed concentrically on the opposite surface of one main surface 25b.

  The cross section of the circular light guide plate 25 is bent in order to increase the reflection angle in the deflection groove 25d while maintaining the directivity of the emitted light. This is because the reflection angle is increased and the total reflection condition is satisfied with a margin to reduce the light transmitted to the back surface without being totally reflected by the deflection groove 25d due to variations in the light flux. It is.

  Even if comprised as mentioned above, a signal apparatus with high directivity and high utilization efficiency of light can be realized, which is useful as a railway signal apparatus. Further, if the cylindrical lens array 22 is also used as in the configuration shown in FIG. 2, it is also useful as a traffic signal.

(Embodiment 2)
In the present embodiment, the only difference from the first embodiment shown in FIG. 1 is the deflection groove of the light guide plate. Therefore, the other components are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted. .

  FIG. 5 is a schematic configuration diagram of the signal display unit 12 of the present embodiment, where (a) is a cross-sectional view of the signal display unit, and (b) is a schematic perspective view of a deflection groove of the light guide plate.

  As shown in FIGS. 5 (a) and 5 (b), the deflection groove 20d of the light guide plate 20 of the present embodiment is formed of a curved surface having a curvature in the Y direction in the drawing, and similarly to the configuration shown in FIG. The inclination with respect to one main surface 20b is formed so as to gradually change between 0 degrees and 45 degrees.

  Further, in the deflection groove 20d, a fine groove 20e that scatters the laser beam 16 in the X direction in the figure is formed on the deflection surface, and this groove 20e becomes finer as the inclination of the deflection surface with respect to one main surface 20b becomes smaller. It is configured.

  When the substantially parallel laser beam 16 traveling in the Y direction in the figure enters the deflection groove 20d configured in this way, the reflection angle in the YZ plane changes according to the inclination angle of the deflection surface of the deflection groove 20d, For example, the emitted lights 26a, 26b, and 26c are obtained. At this time, the emitted lights 26a, 26b, and 26c are further scattered in the X direction by the groove 20e, and the degree of scattering increases in the order of the emitted light 26a, the emitted light 26b, and the emitted light 26c.

  Such emitted light can also be realized by using a light guide plate having a plurality of types of deflection grooves inclined in the Y direction and having a curvature in the X direction as shown in FIG. The deflection groove 20d shown in FIG. 6 is configured such that the radius of curvature in the X direction decreases as the inclination angle with respect to one main surface 20b decreases, and each groove is configured to deflect in a different direction. However, even if such grooves are arranged at high density, emitted light similar to the configuration shown in FIG. 5B can be obtained.

  Next, a description will be given of the reach of the outgoing light 26 emitted from the signal display unit 12 configured as shown in FIG. FIGS. 7A and 7B are explanatory views showing a range in which the outgoing light from the traffic light reaches, wherein FIG. 7A is a schematic perspective view of the traffic light, and FIG. 7B is a top view illustrating the illumination range of the outgoing light.

  As shown in FIGS. 7 (a) and 7 (b), when the signal display unit 12 of the present embodiment is used, the outgoing light 26c traveling downward from the traffic light 10 has a large light distribution in the left-right direction and travels far from the traffic signal 10. Since the outgoing light 26a has little light distribution in the left-right direction, there is little light traveling outside the road periphery, and light can be distributed along the road without waste.

  As described above, the traffic light of the present embodiment can distribute light from the traffic light along the road without waste by configuring the light guide plate so as to obtain a desired emission angle characteristic. In addition, it is possible to realize a traffic signal for roads with high light utilization efficiency, as well as high brightness and low power consumption.

(Embodiment 3)
FIG. 8 shows a schematic configuration of the traffic light 30 in the present embodiment, (a) is a schematic configuration diagram, and (b) is a cross-sectional view seen from the line 8C-8C of (a).

  As shown in FIGS. 8A and 8B, the traffic light 30 of the present embodiment is composed of a light source unit 31 and a signal display unit 32, and the light emitted from the light source unit 31 is signal-displayed by two optical fibers 13. It is configured to lead to the part 32.

  The light source unit 31 includes laser light sources 34a and 34b, a signal control unit 35 for independently controlling light emission / extinction of the laser light sources 34a and 34b, and laser light 36a and 36b emitted from the laser light sources 34a and 34b by two optical fibers. The signal display unit 32 includes a collimating lens 18 for collimating the light emitted from the two optical fibers 13 and the light incident from the incident end surface 19a from the side surface 19b. A light guide rod 19 that emits light to be converted into linear light, a light guide plate 37 that emits light incident from the incident end surfaces 37a on both sides from one main surface 37b, and a reflection disposed adjacent to the light guide plate 37. The configuration includes a sheet 21.

  Here, the laser light sources 34a and 34b are configured such that the emitted laser beams 36a and 36b are substantially the same color by a single color or a mulberry color.

  In addition, a polarization groove 37d that totally reflects incident light and deflects it toward the one main surface 37b is provided on the opposing surface 37c of the one main surface 37b of the light guide plate 37. The deflection groove 37d is provided in parallel to the incident end face 37a, and is configured to deflect and emit light that is incident substantially in parallel while being parallel. Further, the deflection groove 37d has deflection surfaces with different inclination angles with respect to the incident end surfaces 37a on both sides, and is configured to deflect light incident from both sides in different directions.

  Further, the light guide plate 37 is configured to be bent in a V shape as shown in FIG. This is to prevent light incident from the incident end surfaces 37a on both sides from reaching the opposite incident end surface 37a and escaping the light.

  In the traffic light 30 configured as described above, the laser beams 36a and 36b emitted from the laser light sources 34a and 34b are guided through the condenser lens 17, the optical fiber 13, and the collimator lens 18, respectively, and the light guide plate inside the display unit 32. The light is incident on the light guide rods 19 disposed on both sides of the light beam 37 as parallel light, deflected by the deflection groove 19c, and emitted from the side surface 19b as substantially parallel light.

  The laser beams 36a and 36b emitted from the light guide rod 19 are incident substantially in parallel from the incident end surfaces 37a on both sides of the light guide plate 37, are deflected by the deflection grooves 37d, and the laser light 36a is directed downward in the signal display section 32. The laser beam 36 b is emitted toward the front direction of the signal display unit 32.

  FIG. 9 shows a range in which the laser beams 36a and 36b emitted from the signal display unit 32 of the traffic light 30 reach. In this figure, the laser beam 36a is distributed so as to be visible in an area 38 on the road, and the laser beam 36b. Is distributed so that it can be seen in the region 39 on the road.

  The traffic light 30 according to the present embodiment configured as described above can independently control the laser light 36a and the laser light 36b, so that different signals can be displayed in different regions from the traffic light.

  For example, when the signal changes from blue to red, such a traffic light can display a yellow signal in the area 38 near the traffic light and display a red signal early in the area 39 far from the traffic light at the same moment. It is possible to prevent dangerous situations such as rushing to the intersection at the turn of the signal.

  As described above, the traffic light according to the present embodiment can display an appropriate signal according to the distance between the car and the traffic light, such as providing a time difference in switching the signal display near and far from the traffic light. A traffic signal with improved traffic safety or smoothness can be realized.

(Embodiment 4)
FIG. 10 shows a schematic configuration of the traffic light 40 in the present embodiment. As shown in FIG. 10, the traffic light 40 according to the present embodiment includes a light source unit 41, a signal display unit 42, and an optical fiber 13 that guides light emitted from the light source unit 41 to the signal display unit 42. Here, since the light source unit 41 has the same configuration as the light source unit 11 of the first embodiment, the description thereof is omitted.

  In the present embodiment, the signal display unit 42 includes a collimating lens 18 that collimates light emitted from the optical fiber 13, and a composite polarizing prism 43 including a PBS surface 43a and a reflecting surface 43b that transmit P-polarized light and reflect S-polarized light. And a half-wave plate 44 arranged to rotate the polarization of the light transmitted through the PBS surface 43a of the composite polarizing prism 43 by 90 degrees, and the same configuration as that of the first embodiment shown in FIG. The light guide bar 19 and the light guide plate 20 are provided.

  In the signal device 40 configured as described above, the laser light 16 emitted from the light source unit 41 is emitted as random polarized light through the optical fiber 13 and passes through the collimator lens 18 to be inside the signal display unit 42. Is incident on the composite polarizing prism 43. Of the laser light 16 incident on the composite polarization prism 43, the P-polarized component (polarized light in the direction parallel to the paper surface) is transmitted through the PBS surface 43a, and the S-polarized component (polarized light in the direction perpendicular to the paper surface) is transmitted through the PBS surface 43a. The light reflected and reflected by the PBS surface 43a is further reflected by the reflection surface 43b and exits from the composite polarizing prism 43, respectively.

  Of the laser light 16 emitted from the composite polarizing prism 43, the light transmitted through the PBS surface 43a is rotated by 90 degrees by the half-wave plate 44, and is perpendicular to the same paper surface as the light reflected by the PBS surface 43a. The polarized light enters the light guide bar 19.

  Here, the deflection surface of the deflection groove 19c of the light guide bar 19 is parallel to the polarization of the laser light 16 incident on the light guide bar 19, so that the laser light 16 is completely polarized without being disturbed by the deflection groove 19c. The light is reflected and emitted from the light guide rod 19 while being polarized perpendicular to the paper surface, and enters the light guide plate 20.

  Here, since the deflection surface of the polarization groove 20d of the light guide plate 20 is perpendicular to the polarization surface of the incident laser beam 16, the laser beam 16 is totally reflected without disturbing the polarization, and is polarized in the vertical direction in the figure. And emitted.

  FIG. 11 is an explanatory diagram showing a scene where the traffic signal 40 is used, and shows a case where the sun 46 is behind the signal display unit 42. In the case as shown in this figure, the laser beam 16 and the sunlight 47 emitted from the signal display unit 42 enter the field of view from substantially the same direction, which is very dazzling and it is difficult to visually recognize the signal.

  At this time, when the signal display unit 42 is viewed through the polarizing plate 45 using the polarizing plate 45 that transmits only the polarization component in the vertical direction instead of the sunshade of the driver's seat, the brightness of the laser light 16 does not decrease. Since the brightness of the light 47 is halved, it becomes easier to visually recognize the signal display.

  Alternatively, like the display surface of the signal display unit 42 shown in FIG. 12, a retardation film having the function of a half-wave plate is disposed in the areas 48a, 48b, and 48c that represent symbols corresponding to signal colors. If the other regions and the polarization are orthogonal to each other, the symbols appear to be floating when viewed through polarized glasses or the like, so that it is possible to prevent misperception of color blind persons (color blindness, color weakness).

  As described above, the signal device according to the present embodiment uses the laser light source to obtain output light having a uniform polarization with high light utilization efficiency, so that the signal display unit and the sun overlap with each other. Visibility can be improved. Furthermore, it is possible to realize a traffic light that prevents a color blind person from being misidentified.

  In this embodiment, linearly polarized light is emitted. However, a quarter wavelength plate may be further disposed on the display surface of the signal display unit to emit circularly polarized light. In this case, the same effect as this embodiment can be obtained by viewing the traffic light through the quarter-wave plate and the polarizing plate. In this case, when glasses comprising a quarter wavelength plate and a polarizing plate are used, the appearance of the signal does not change even if the face is tilted.

  Since the traffic light of the present invention uses a laser light source, it is possible to realize a traffic light with high directivity, low power consumption and high brightness. If it is used as a traffic signal for railways, it is possible to avoid the risk of misrecognizing signals other than the intended lane. Furthermore, since light with uniform polarization can be emitted efficiently, the use of a polarizing filter or the like can improve visibility and prevent misperception of a color blind person.

(A) Schematic configuration diagram of the traffic light in the first embodiment of the present invention, schematic configuration diagram (b) Sectional view seen from line 1C-1C of (a) The enlarged view of another form of the deflection | deviation groove | channel in Embodiment 1 of this invention Sectional drawing of another form of the signal display part in Embodiment 1 of this invention (A) Sectional drawing seen from the 4C-4C line | wire of schematic block diagram (b) (a) with the schematic block diagram of another form of the traffic light in the 1st Embodiment of this invention (A) Schematic configuration diagram of a signal display unit according to the second embodiment of the present invention and a sectional view (b) Schematic perspective view of a deflection groove Schematic perspective view of another form of the deflection groove in Embodiment 2 of the present invention (A) It is explanatory drawing which showed the range which the emitted light from the signal apparatus of Embodiment 2 of this invention reaches, and is a schematic perspective view of a signal apparatus (b) The top view explaining the illumination range of the emitted light (A) Schematic configuration diagram of the traffic light in Embodiment 3 of the present invention, schematic configuration diagram (b) Sectional view seen from line 1C-1C in (a) Explanatory drawing which showed the range which the emitted light from the traffic light of the 3rd Embodiment of this invention reaches Schematic configuration diagram of a traffic light in the fourth embodiment of the present invention Explanatory drawing which showed the utilization scene of the traffic light in the 4th Embodiment of this invention The block diagram which showed the other form of the display surface of the signal display part in the 4th Embodiment of this invention The schematic block diagram of the other form of the traffic light in the 1st Embodiment of this invention

Explanation of symbols

10, 30, 40, 50 Traffic light 11, 31, 41 Light source unit 12, 32, 42 Signal display unit 13 Optical fiber 14, 34a, 34b Laser light source 15, 35 Signal control unit 16, 36a, 36b Laser beam 17 Condensing lens 18 collimating lens 19 light guide rod 19a incident end face 19b side face 19c deflection groove 20, 37 light guide plate 20a, 37a incident end face 20b, 37b one main surface 20c, 37c opposing face 20d, 37d deflection groove 20e groove 21 reflecting sheet 22 cylindrical lens Array 24 Ring-shaped light guide 24a Incident end face 24c Deflection groove 25 Circular light guide 25a Side surface 25b One main surface 25d Deflection groove 26, 26a, 26b, 26c Emission light 38, 39 Area 43 Compound polarization prism 43a PBS surface 43b Reflection Surface 44 Half-wave plate 45 Polarizing plate 4 6 Sun 47 Sunlight 48a, 48b, 48c Phase difference film 51 Diffuser element 52 Reflector plate 53 Fresnel lens

Claims (14)

A light source that emits laser light;
A surface light emitting unit that emits light emitted from the light source in a planar shape;
An optical fiber for guiding light from the light source to the surface light emitting unit;
A signal control unit for controlling light emission and extinction of the light source;
A traffic light characterized by comprising: The surface light emitting unit is a linear light guide unit that linearly spreads and emits laser light emitted from the optical fiber, and
A light guide plate that makes laser light emitted from the linear light guide part incident from the side surface and is emitted from one main surface; and
With
The linear light guide is configured to emit substantially parallel light,
The light guide plate has a deflection groove for deflecting incident light toward the one main surface on a surface opposite to the one main surface, and the deflection groove is formed in parallel to the incident surface on which light enters. The traffic light according to claim 1, wherein The surface light emitting unit is a ring-shaped light guide unit that converts laser light emitted from the optical fiber into a ring-shaped light beam,
A circular light guide plate that makes the laser light emitted from the ring-shaped light guide part incident from the outer peripheral side surface and is emitted from one main surface, and
The traffic light according to claim 1, wherein the ring-shaped light guide is configured to emit light from the inner peripheral side surface toward the center. The surface light emitting unit includes a cylindrical lens array adjacent to the one main surface of the light guide plate,
4. The traffic light according to claim 2, wherein light emitted from the light guide plate is diffused in a one-dimensional direction by the cylindrical lens array. 5. The deflection groove of the light guide plate has a curved deflection surface, and the deflection surface is configured such that an inclination angle with respect to the one main surface gradually changes between 0 degrees and 45 degrees. The traffic light according to claim 2. The deflection groove of the light guide plate is composed of various types of deflection grooves having different inclination angles with respect to the one main surface of the deflection surface, and the deflection surface of each deflection groove has an inclination angle with respect to the one main surface of 0 to 45 degrees. The traffic light according to claim 2, wherein the traffic light is configured in degrees. The deflection surface of the deflection groove has a diffusion groove for diffusing light in a direction perpendicular to the direction in which the deflection surface has a curvature, and the diffusion groove has a smaller inclination angle with respect to the one main surface of the deflection surface. 6. The traffic light according to claim 5, wherein the traffic light is configured to spread widely. The deflection surface of the deflection groove has a curvature in a direction orthogonal to the direction in which the deflection surface is inclined with respect to the one main surface, and diffuses more widely as the inclination angle of the deflection surface with respect to the one main surface is smaller. The traffic light according to claim 6, wherein the traffic light is configured as follows. At least two laser light sources emitting laser light of the same wavelength;
A signal controller for independently controlling light emission and extinction of the at least two laser light sources;
A surface light emitting unit that makes laser beams emitted from the at least two laser light sources incident on each of the laser beams and spreads them in a planar shape; and
3. The traffic light according to claim 2, wherein the laser beams emitted from the at least two laser light sources are emitted with directivity at different angles from the surface light emitting units. The light guide plate is configured such that laser light is incident from the side surfaces on both sides,
10. The traffic light according to claim 9, wherein the deflection groove of the light guide plate has two deflection surfaces that deflect at different angles according to the direction in which light enters. 3. The traffic light according to claim 2, wherein the emitted light is linearly polarized light or circularly polarized light. The surface light emitting unit has a region where the polarization of the emitted light is orthogonal to the polarization of the light emitted from other regions,
The traffic light according to claim 11, wherein the region is configured to have a predetermined symbol shape corresponding to a color of light emitted from the surface light emitting unit. 2. The surface emitting unit includes a diverging element that uniformly spreads laser light emitted from an optical fiber, and a collimating element that imparts a predetermined light distribution characteristic to the laser light emitted from the diverging element. The traffic light described. The laser light source has a laser light source that emits red and green laser light,
The traffic light according to any one of claims 1 to 13, wherein the red laser light and the green laser light are guided to a surface light emitting unit for a yellow signal.

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