JP2015179603A - Light emission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new light emission device.SOLUTION: A light emission device has: a light source for emitting light on an optical axis; and at least one mirror element arranged being inclined with respect to the optical axis. The mirror element includes: first and second transparent substrates arranged oppositely; first and second transparent electrodes formed above the opposing surfaces of the first and second transparent substrates; and electrolyte including an electrodeposition material containing metal ions arranged between the first and second transparent electrodes. Furthermore, the light emission device has a control circuit for applying a voltage between the first and second transparent electrodes of the mirror element.

Description

  The present invention relates to a light emitting device such as a vehicular lamp or various lighting fixtures.

  In a light emitting device, for example, a car tail lamp or turn signal, by sequentially lighting a plurality of light emitting areas sequentially, the visibility of the driver of the following vehicle can be improved as compared with the case of lighting a single light emitting area. It becomes possible. There has been proposed a tail lamp in which a large number of light emitting diodes arranged in a matrix are sequentially turned on in accordance with a signal input from a control device (for example, Patent Document 1).

  When an electrolytic solution containing an electrodeposition material containing silver ions is contained in a cell having a counter electrode and a voltage is applied between the counter electrodes, silver is deposited and deposited by a reduction reaction on the electrode surface on the negative potential side. Can be formed. Further, by adding a salt of copper (II) ions as a mediator to the electrolyte, it is possible to accelerate the silver oxidation reaction when no voltage is applied and dissolve the precipitated silver (for example, Patent Document 2).

JP 6-51453 JP2012-181389

  A novel light emitting device is provided.

  According to one aspect of the present invention, a light source that emits a light beam on an optical axis, and at least one mirror element that is disposed to be inclined with respect to the optical axis, the mirror element is disposed to face each other. Between the first and second transparent electrodes, the first and second transparent electrodes formed above the opposing surfaces of the first and second transparent substrates, and the first and second transparent electrodes And a control circuit for applying a voltage between the first and second transparent electrodes of the mirror element, and an electrolyte solution containing an electrodeposition material containing metal ions. Is done.

1A is a cross-sectional view showing the cell structure of the mirror element in the transmission state, and FIG. 1B is a cross-sectional view showing the cell structure of the mirror element in the reflection state. FIG. 2A is a schematic diagram of a measurement system for measuring the reflectance and transmittance of the mirror element, and FIGS. 2B, 2C, and 2D are graphs showing the transmittance, reflectance, and transmittance spectrum of the mirror element. and 3A is a cross-sectional view showing a structure of a light emitting device including a light source and four mirror elements, and FIGS. 3B to 3F are cross-sectional views showing operations of the light emitting device of FIG. 3A. and 4A is a sectional view showing a light emitting device in which the tilt angle with respect to the optical axis of the mirror element of the light emitting device is set to a different angle for each mirror element, and FIGS. 4B to 4F are cross sections showing the operation of the light emitting device in FIG. 4A. FIG. FIG. 5A is a cross-sectional view showing a wiring between a mirror element that can divide the first transparent electrode into four parts and can form a silver thin film on the surface of each divided electrode and the control circuit, and FIGS. 5B and 5C are selectively in a reflective state. It is sectional drawing which showed the emission control of the light by a mirror element. FIG. 6A is a cross-sectional view showing the operation of the light emitting device composed of the light source and one mirror element arranged on the optical axis, and FIG. 6B shows the operation of the light emitting device arranged with a plurality of mirror elements on the optical axis. It is sectional drawing shown. FIG. 7A is a cross-sectional view showing a lighting device that can selectively control a mirror element that is in a reflecting state, and FIG. 7B is a diagram showing a pedestrian lighting operation of the lighting device of FIG. 7A. , , and 8A is a perspective view showing a microprism formed on a transparent substrate, FIGS. 8B to 8F are cross-sectional views showing a process of forming a microprism on the transparent substrate and a transparent electrode on the microprism, and FIG. 8H is a cross-sectional view showing a microprism reflector with a metal electrode, FIG. 8I is a cross-sectional view showing the structure of the mirror element with the microprism electrode surface in a reflective state, and FIG. Is a cross-sectional view showing the direction of reflected light when light is incident on the mirror element of FIG. 8I from the normal direction, FIG. 8K is a cross-sectional view showing the structure of the mirror element in which the flat transparent electrode surface of the mirror element is in a reflective state, 8L is a cross-sectional view showing the direction of reflected light when light enters the mirror element of FIG. 8K from the normal direction, and FIG. 8M adopts the mirror element and the reflector in the illumination device of FIG. 7A. Sectional view showing a light device, FIG. 8N is a sectional view of the lighting device of FIG. 8M shows a direction capable of emitting light.

  DESCRIPTION OF SYMBOLS 3 ... Electrolyte solution, 7 ... Silver thin film, 11 ... 1st transparent substrate, 12 ... 1st transparent electrode, 12a ... 1st division | segmentation electrode, 12b ... 2nd division | segmentation Electrode, 12c ... 3rd divided electrode, 12d ... 4th divided electrode, 13 ... Microprism, 13a ... Microprism material resin, 14 ... Seal material, 15 ... DC power supply, 16 ... Gap control agent, 17 ... SUS mask, 18 ... Quartz plate, 19 ... Micro prism mold, 21 ... Second transparent substrate, 22 ... Second transparent electrode 32 ... Metal electrode, 40 ... Rear window, 41 ... Control circuit, 42 ... Light source, 43 ... Mirror element, 43a ... First mirror element, 43b ... Second Mirror element, 43c ... third mirror element, 43d ... fourth mirror 45 ... mirror or light absorbing plate, 46 ... transparent plate, 47 ... mirror, 48 ... microprism reflector with metal electrode, 60 ... reflection of light reflected by mirror on flat surface Direction, 61 ... Direction of light reflected by mirror on microprism electrode, 62 ... Direction of light reflected by metal mirror on flat surface, S ... Human sensor, S1 ... First human sensor, S2 ... 2nd person sensor, S3 ... 3rd person sensor, S4 ... 4th person sensor, S5 ... 5th person sensor.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1A is a cross-sectional view showing the cell structure of the mirror element 43 in the transmissive state. In addition, the relative size of each structure shown in a figure differs from an actual thing.

  First and second transparent substrates 11 and 21 having first and second transparent electrodes 12 and 22 on the surface are prepared. Glass or the like is used for the first and second transparent substrates 11 and 21. Indium tin oxide (ITO) or the like is used for the first and second transparent electrodes 12 and 22. The first and second transparent electrodes 12 and 22 may be formed on the surfaces of the first and second transparent substrates 11 and 21 by a method such as sputtering, chemical vapor deposition (CVD), or vapor deposition. If necessary, the first and second transparent electrodes 12 and 22 may be patterned.

  The first transparent substrate 11 and the second transparent substrate 21 are arranged to face each other so that the first and second transparent electrodes 12 and 22 face each other. A gap control agent is used to control the gap between the first and second transparent substrates 11 and 21 arranged opposite to each other. The size of the gap is from 20 microns to several hundred microns (eg, 100 microns). In the example, the gap control agent was sprayed so as to be 1-3 pieces / mm 2, but it is desirable that the spraying amount be set so as not to affect the display according to the gap diameter. In the case of this example, even if there is some gap unevenness, since the influence on the display is small, the spread amount is not so important.

  In this example, the gap control is performed by the gap control agent, but the gap control may be performed by a protrusion such as a rib. In the case of a small cell, the gap may be controlled by using a spacer on a film having a predetermined thickness at the seal portion.

  An ultraviolet (UV) and thermosetting sealing material 14 is applied on one transparent substrate, an electrolytic solution 3 containing an electrodeposition material containing silver ions is dropped on one transparent substrate, and both substrates are stacked. Combined. The sealing material 14 was cured by irradiating with ultraviolet rays.

  The sealing material 14 may be a photocuring type or a thermosetting type. A seal material that is resistant to electrolyte (a seal material that does not corrode) is preferred.

  The electrolyte 3 is a compound containing silver which is an electrodeposition material such as AgNO 3, an electrolyte such as tetrabutylammonium bromide (TBABr), a mediator such as CuCl 2, and an electrolyte purifying agent (supporting electrolyte) such as LiBr. And a solvent such as dimethyl sulfoxide (DMSO). The electrolyte is not limited to a silver compound that becomes silver ions, but may be a metal compound that becomes metal ions such as Cu, Mg, Ni, Ru, Rh, Pd, Os, Ir, Pt, Au, and Al. .

  AgNO3 is added as a 50 mM electrochromic agent, LiBr is added as a 250 mM supporting electrolyte, and CuCl2 is added as a 10 mM mediator in the solvent DMSO. PVB may be added to the electrolyte as a 10 wt% host polymer, but in this example, an electrolyte that does not gel is used.

  The supporting electrolyte is not limited as long as it promotes the redox reaction or the like of the color developing material. For example, lithium salt (LiCl, LiBr, LiI, LiBF4, LiClO4, etc.), potassium salt (KCl, KBr, KI, etc.), sodium A salt (NaCl, NaBr, NaI, etc.) can be preferably used. The concentration of the supporting electrolyte is preferably 10 mM or more and 1 M or less, but is not particularly limited.

  The solvent is not limited as long as it can stably hold the coloring material and the like. Polar solvents such as water and propylene carbonate, non-polar organic solvents, ionic liquids, ionic conductive polymers, polymer electrolytes, and the like can be used. Specifically, propylene carbonate, dimethyl sulfoxide, N, N-dimethylformamide, tetrahydrofuran, acetonitrile, polyvinyl sulfate, polystyrene sulfonic acid, polyacrylic acid and the like can be used.

  A one-drop filling (ODF) process was used for the process of dropping an appropriate amount of the electrolytic solution 3 on the surface of either the first transparent substrate 11 or the second transparent substrate 21. As a dropping method, various printing methods including a dispenser and an ink jet can be applied.

  Both transparent substrates were superimposed in a vacuum (or in the air or in a nitrogen atmosphere). Thereafter, the sealing material 14 was cured by irradiating the sealing portion with ultraviolet rays (for example, 6 J / cm 2). A stainless steel (SUS) mask or the like was used so that only the seal portion was exposed to light.

  The cell of the manufactured mirror element 43 was almost transparent. Although it was slightly yellowish, it is thought that the color of the mediator, CuCl2, appears. It can be improved by changing the material of the mediator or reducing the cell thickness. Since the cell of this example was manufactured with a thin cell thickness, the yellowness was thin. In addition, the responsiveness was relatively fast.

  FIG. 1B shows that the silver thin film 7 is deposited on the surface of the first transparent electrode 12 which is a negative electrode by applying a DC voltage from the DC power source 15 between the first and second transparent electrodes 12 and 22 of the mirror element 43, and reflected. It is sectional drawing which showed the mirror element made into the state.

  When the first transparent electrode 12 is a negative electrode and the second transparent electrode 22 is a positive electrode, a reduction reaction of silver ions contained in the electrolytic solution 3 occurs on the surface of the first transparent electrode 12 that is a negative electrode. Silver thin film 7 is deposited. By the formed silver thin film 7, the light incident on the mirror element in the reflective state is reflected.

  The light incident from the second transparent electrode 22 side is partially attenuated when passing through the electrolytic solution 3 accommodated between the first and second transparent electrodes 12 and 22. The negative electrode of the mirror element in the reflecting state constituting the light emitting device to be described later may be set as a transparent electrode on the light source side.

  In addition, although the magnitude | size of the DC voltage to apply is about 1.5V-8V, it changes with the magnitude | sizes and materials of an electrode.

  When the voltage is turned off or a reverse polarity voltage is applied, the silver thin film 7 dissolves in the electrolytic solution 3 and returns to the transparent state. The response is faster when a reverse polarity voltage is applied.

  As described above, the mirror element 43 whose manufacturing process has been described is used in the light emitting devices in the following embodiments.

  The transmittance and reflectance of the mirror element were measured. By making light incident on the reflection probe from a halogen light source and observing the reflected light with a spectroscope, the transmittance and the reflectance of the mirror element in the transmission state and the reflection state were spectroscopically measured. Measurement was performed by applying a DC voltage of 2.5 V between the first and second transparent electrodes 12 and 22 of the mirror element. As shown in FIG. 2A, a DC voltage was applied from a DC power source 15 so that the silver thin film 7 was formed on the transparent electrode on the light incident side.

  2B and 2C are graphs showing changes in transmittance and reflectance of a mirror element in a transmissive state and a mirror element in a reflective state in which a silver thin film is deposited by applying a DC voltage of 2.5V. The horizontal axis indicates wavelength in units (nm), and the vertical axis indicates transmittance T and reflectance R in units (%). A solid line indicates a silver thin film dissolution (transmission) state, and a broken line indicates a silver thin film deposition (reflection) state. The reflection spectrum in the reflection state shows almost specular reflection outside the near ultraviolet region. This is because the silver ions in the electrolytic solution 3 are reduced in the vicinity of the transparent electrode, which is a negative electrode, and are converted into metallic silver and deposited and deposited. When the voltage application is stopped (0 V or open state), the mirror element in the reflective state returns to the mirror element in the transmissive state. A reverse bias voltage (for example, -1 V) may be applied. By applying the reverse bias voltage, the mirror element in the reflective state can be returned to the mirror element in the transparent state earlier than when the voltage application is stopped.

  The transmittance spectrum in FIG. 2B is slightly wavelength dependent. The cell of the mirror element 43 was yellowish. This appears to be the color of the mediator CuCl2. In this example, a cell having a cell thickness of 100 microns is used, and it can be improved by reducing the cell thickness.

  FIG. 2D is a graph showing a transmittance spectrum of a mirror element in a transmissive state using a DMF material as a solvent (the cell thickness here is 50 microns). Compared with the graph of FIG. 2B which shows the transmittance spectrum of the mirror element in the transmission state using DMSO which shows wavelength dependency as a solvent, the transmittance is high even for light of a short wavelength. It is considered that the transmittance unevenness due to the wavelength of light can be reduced by using the DMF material as the solvent.

Example 1
Hereinafter, a light emitting device used as a sequential turn signal for continuously lighting a plurality of regions will be described.

  FIG. 3A shows a light source 42 that emits light on the optical axis, and mirror elements of four cells (first, second, third, and fourth cells) that are arranged on the optical axis and inclined with respect to the optical axis direction. The light-emitting device which has 43a, 43b, 43c, 43d is shown. The control device 41 can apply a voltage between the first and second transparent electrodes 12 and 22 of each mirror element.

  The turn signal light source 42 is a light source capable of emitting at least amber light. Light sources of other colors such as red and white may be used. The light from the light source 42 may be collimated to some extent using a reflector or a lens. The first, second, third, and fourth mirror elements 43a, 43b, 43c, and 43d are arranged so as to be inclined at a certain angle (for example, 45 degrees) with respect to the optical axis of the light emitted from the light source 42. The first and second transparent electrodes 12 and 22 of each mirror element are electrically connected to the control circuit 41, respectively, and a direct current voltage is applied between the first and second transparent electrodes of each mirror element. The silver thin film 7 is formed on the surface of the transparent electrode on the light source 42 side by using the transparent electrode on the 42 side as a negative electrode. The light emitted from the light source 42 by the silver thin film 7 is reflected and emitted to the outside.

  A mirror (fixed mirror) 47 inclined at the same angle as each mirror element may be disposed on the optical axis extension line of each mirror element disposed. Even if all the mirror elements (variable mirrors) break down, the light emitted from the light source 42 is reflected by the mirror 47 and emitted outside the light emitting device, so that it can function as a winker. This is desirable for fail-safe purposes.

  A transparent plate 46 is disposed on the light emitting side of the light emitting device through which the reflected light passes. The transparent plate 46 may be provided with a light scattering function or a function for controlling light distribution to some extent by lens cutting. A mirror or a light absorbing plate 45 may be disposed on the back side of the light emitting device. 3B to 3F are cross-sectional views illustrating the operation of the light emitting device. Note that two wirings connecting the first and second transparent electrodes 12 and 22 and the control circuit 41 of each mirror element described in FIG. 3A are simplified and shown as one in the following drawings.

  The light emitted from the light source 42 passes through the transmitting mirror element, is reflected by the first reflecting mirror element, and is emitted outside the light emitting device. When all the mirror elements are in the transmissive state, as shown in FIG. 3F, the light emitted from the light source 42 passes through all the mirror elements 43 that are in the transmissive state and is reflected by the mirror 47 disposed behind the mirror elements 43. The light is emitted to the outside of the light emitting device.

  FIG. 3B is a cross-sectional view showing the operation of the light emitting device when a direct current voltage is applied between the first and second transparent electrodes 12 and 22 of the first mirror element and the first mirror element 43a is in a reflective state. is there. The light emitted from the light source 42 is reflected by the first mirror element 43a in the reflective state and is emitted to the outside of the light emitting device. Although it is indicated that the second to fourth mirror elements are mirror elements in the transmissive state, there is no difference in operation even in the reflective state. Since the light does not reach the back of the mirror element in the reflective state, the light distribution is not affected.

  FIG. 3C is a cross-sectional view showing the operation of the light emitting device when a DC voltage is applied between the first and second transparent electrodes 12 and 22 of the second mirror element and the second mirror element 43b is in a reflecting state. is there. The first mirror element is in a transmissive state. The light emitted from the light source 42 passes through the first mirror element 43a, is reflected by the second mirror element 43b in a reflective state, and is emitted outside the light emitting device.

  FIG. 3D is a cross-sectional view showing the operation of the light emitting device when a DC voltage is applied between the first and second transparent electrodes 12 and 22 of the third mirror element to bring the third mirror element 43c into a reflective state. It is. The first and second mirror elements are in a transmissive state. The light emitted from the light source 42 passes through the first and second mirror elements 43a and 43b, is reflected by the third mirror element 43c in the reflective state, and is emitted outside the light emitting device.

  FIG. 3E is a cross-sectional view showing the operation of the light emitting device when a DC voltage is applied between the first and second transparent electrodes 12 and 22 of the fourth mirror element to bring the fourth mirror element 43d into a reflective state. is there. The first, second, and third mirror elements are in a transmissive state. The light emitted from the light source 42 passes through the first, second, and third mirror elements 43a, 43b, and 43c, is reflected by the fourth mirror element 43d that is in the reflective state, and is emitted to the outside of the light emitting device.

  FIG. 3F is a cross-sectional view illustrating the operation of the light emitting device when the first, second, third, and fourth mirror elements 43a, 43b, 43c, and 43d are in a transmissive state. The light emitted from the light source 42 passes through the first, second, third, and fourth mirror elements 43a, 43b, 43c, and 43d, and is reflected by the mirror 47 disposed on the optical axis behind each mirror element. The light is emitted to the outside of the light emitting device.

This light emitting device can constitute a sequential turn signal that moves the position of the light emitting part sequentially (continuous), and requires a plurality of light sources or a mechanical structure that mechanically moves the light sources. Compared with a conventional sequential turn signal, a sequential turn signal can be realized with one light source and a plurality of electrically controllable mirror elements arranged on the optical axis.
(Modification 1)
FIG. 4A shows that the tilt angles with respect to the optical axes of the first, second, third, and fourth mirror elements 43a, 43b, 43c, and 43d in the respective transmission states constituting the light emitting device shown in FIG. 3A are all the same. FIG. 5 is a cross-sectional view showing a modification example with different angles. In order to distribute the emitted light over a wide range, it may be preferable to gradually increase or decrease the tilt angle of the mirror element with respect to the optical axis. However, it is not limited to changing the tilt angles of the plurality of mirror elements one by one, but two or more mirror elements having the same tilt angle may be continuous.

  For example, the first mirror element 43a has an angle between its normal and the optical axis of 30 °, the second mirror element 43b has an angle between the normal and the optical axis of 37.5 °, and the third mirror element 43c has its normal. The angle between the optical axis and the optical axis is 45 °, the angle between the normal line and the optical axis of the fourth mirror element 43d is 52.5 °, the angle between the normal line and the optical axis of the terminal mirror 47 is 60 °, etc. It is also good. The angle may be decreased sequentially. The angle can be changed depending on the application. The state of the light emitting device shown in FIGS. 4B to 4F can be realized by selectively applying a DC voltage between the first and second transparent electrodes of each mirror element to bring each mirror element into a reflective state. By changing the tilt angle, light distribution over a wide range is realized. If the light distribution range is the same, the number of mirror elements to be arranged may be reduced.

This modification may be applied to a cornering lamp when used as an auxiliary light source for a headlamp. It is considered that a safe cornering lamp can be realized by changing the irradiated portion as shown in FIGS. 4B to 4F according to the turning angle of the handle.
(Modification 2)
In FIG. 5A, the transparent electrode 12 shown on the lower side is divided into four first, second, third, and fourth divided electrodes 12a, 12b, 12c, and 12d, and the transparent electrode 22 shown on the upper side is used as a common electrode. FIG. 5 is a cross-sectional view showing a configuration in which each transparent electrode of the mirror element 43 and a control circuit 41 are connected by five wires. By applying a DC voltage having the divided electrode as a negative electrode from the control circuit 41 between the divided electrodes 12a, 12b, 12c, 12d and the common transparent electrode 22, the silver thin film 7 is formed on the surface of the divided electrode, can do.

  The 4-dot pattern of the divided electrode shown in FIG. 5A was manufactured as a pattern having an electrode width of 30 mm and an interelectrode distance of 50 microns, for example. The number, width, and interval are not limited to these. For example, the size may be a size that can be recognized by a driver such as a succeeding vehicle as a winker.

  5B and 5C are cross-sectional views for explaining the operation of the configuration in which four mirror elements having the divided electrodes shown in FIG. 5A are arranged on the optical axis and a mirror (fixed mirror) 47 is arranged on the optical axis behind the mirror elements. It is. 5B shows the second, third, and fourth divided electrodes 12b, 12c, and 12d of the first mirror element 43a and the common transparent electrode 22, and the first divided electrode 12a and the common transparent electrode 22 of the second mirror element 43b. 2 shows the light distribution in the case where a DC thin film is applied to each divided electrode as a negative electrode and a silver thin film is deposited on the divided electrode to which the voltage is applied. A region from the second divided electrode of the first mirror element 43a to the first divided electrode of the second mirror element 43b constitutes a reflective region, and the emitted light is directed downward in the drawing.

  FIG. 5C shows the third and fourth divided electrodes 12c and 12d of the first mirror element 43a and the common transparent electrode 22, and the first and second divided electrodes 12a and 12b and the common transparent electrode 22 of the second mirror element 43b. 3 shows the light distribution when a DC thin film is applied to each divided electrode as a negative electrode and a silver thin film is deposited on the divided electrode to which the voltage is applied. The region from the third divided electrode of the first mirror element 43a to the second divided electrode of the second mirror element 43b constitutes a reflective region, and the emitted light is directed downward in the drawing. When the state of FIG. 5C is displayed after the state of FIG. 5B, the light emission region will appear to move to the right for the observer located in the lower part of the figure.

  5B and 5C, the wiring between the mirror element 43 and the control circuit 41 shown in FIG. 5A is shown in a simplified manner. The mirror elements 43a, 43b, 43c, and 43d are preferably arranged so that the mirror elements can be seen adjacent to each other when viewed from the light emitting side.

  In this way, one transparent electrode of the mirror element is divided into a plurality of dot electrodes, and the divided electrode is formed by selectively applying a DC voltage to each dot electrode using the dot electrode as a negative electrode to deposit a silver thin film. The mirror region can be set in units of dot electrodes obtained by further dividing the divided electrode, and finer light emission control can be realized. Note that the common electrode may be divided in accordance with the dot electrode. Although the number of wirings increases, it may be effective in reducing leakage current.

  When used for a hazard lamp, it may be lit so that each light distribution flows inward in synchronization with the turn signal on the opposite side. Alternatively, the first divided electrode 12a of the first mirror element 43a, the second divided electrode 12b of the second mirror element 43b, the third divided electrode 12c of the third mirror element 43c, the fourth divided electrode 12d of the fourth mirror element 43d, and the respective A hazard display may be performed in which a voltage is applied between the second transparent electrodes 22 of the mirror elements, each divided electrode is set as a negative electrode, each mirror element is partially reflected, and the light source 42 blinks.

  Although the case of the turn signal is shown here, it may be used for light distribution of a stop lamp or a back lamp. The light distribution of the stop lamp may be changed depending on how the driver brakes. Whether or not such light distribution should be performed depends on laws and regulations, but light distribution control that alerts the driver of the following vehicle is desirable.

  The mirror formation responsiveness of the mirror element 43 used here was 0.5 seconds even under normal driving, and switched at a higher speed when a pulse waveform was applied. Therefore, it can be applied to turn signals of automobiles and light distribution control of headlamps.

In addition, although the case where the division | segmentation pattern number of the transparent electrode of the mirror element was set to 4 was described, the number of division | segmentation patterns is not restricted to this. Further, the counter transparent electrode may be divided.
(Example 2)
FIG. 6A shows a light source 42 that supplies a light beam on the optical axis, a mirror element 43 that is disposed obliquely with respect to the optical axis, and a control circuit 41 that applies a voltage, which are installed in a rear window 40 of the automobile. It is sectional drawing which shows operation | movement of the comprised light-emitting device. Note that two wirings connecting the first and second transparent electrodes 12 and 22 of the mirror element and the control circuit 41 are simplified and shown as one in the following drawings. For example, a red light source is used as the light source 42. The transparent plate 46 may be attached to the light emitting side and the opposite side of the light emitting device. The transparent plate 46 may be omitted. A mirror or a light absorbing plate 45 may be attached around the light source 42. In addition, it is desirable to devise a reflector near the light source 42 or a lens disposed on the light source optical axis so that the light from the light source 42 is emitted as close to parallel light as possible.

  The control circuit 41 is arranged at a location that is not a transparent portion of the rear window 40 as is the case with the light source 42. The mirror element 43 is in a transmissive state when no voltage is applied. Therefore, the driver can obtain a good rear view even if these devices are arranged.

  When the driver steps on the brake, the light source 42 is turned on in synchronization therewith. Then, the light emitted from the light source 42 is applied to the mirror element 43 that is in a transmissive state. At this time, in synchronization with the brake, a voltage having the transparent electrode on the light source side as a negative electrode is applied between the first and second transparent electrodes 12 and 22 of the mirror element 43 from the control circuit 41, thereby causing the mirror element 43. Is in a reflective state. As shown in FIG. 6A, the light emitted from the light source 42 is reflected by the mirror element 43 in the reflective state, the traveling direction is changed, and the light is emitted toward the rear window 40. As a result, the brake lamp is recognized in the following vehicle.

  The response speed of the mirror element is about 0.1 to 0.5 seconds, which is slower than the lighting speed of the light emitting diode. Therefore, the light emitted from the light source 42 is transmitted through the transmissive mirror element 43 at the moment of stepping on the brake, but the light irradiation position (angle) of the light source 42 is hindered by the driver, for example, the ceiling in the vehicle. There is no safety problem if it hits the part that does not become. Further, a weak light scattering function may be added to the transparent plate 46 on the rear window 40 side.

  Although the case of using one mirror element has been described, a plurality of mirror elements may be arranged on the optical axis as shown in FIG. 6B.

  In the configuration of FIG. 6B, four mirror elements 43a to 43d are arranged on the optical axis. The first and second mirror elements are in the transmissive state, the third mirror element 43c is in the reflective state, reflects the light emitted from the light source 42, and the light from the brake lamp is emitted from the rear window 40 to the outside rear. It is sectional drawing of a state. By changing (scanning) the mirror element that reflects (first) the light emitted from the light source 42, the light emission position can be changed.

  Furthermore, the first, second, third, and fourth mirror elements 43a, 43b, 43c, and 43d can be formed into half mirrors in which the light transmittance and the reflectance are within a predetermined range by the applied voltage. Therefore, by making each mirror element in FIG. 6B into a half mirror (partially transmitting / partially reflecting state), it is possible to create a light quantity emitted from each position of each mirror element. In addition, depending on the vehicle height and distance of the following vehicle, the height at which the brake lamp is lit is changed by recognizing some of the mirror elements 43a, 43b, 43c, and 43d. It is also possible to make it easier. Specifically, a mirror device to be mirrored can be selected by sensing the height of the following vehicle using a sensor or the like for monitoring the rear (in conjunction with the rear monitor) and sending the information to the control circuit 41.

  Furthermore, depending on the strength with which the driver steps on the brake, a direct voltage of a predetermined pattern is applied between the opposing transparent electrodes of each mirror element to create a reflective state, so that the emitted light intensity and lighting position of the brake lamp can be adjusted over time. It is possible to make it easier to recognize by the driver of the following vehicle.

In FIG. 6B, each mirror element is shown to have a different inclination angle with respect to the optical axis, but the inclination angle of each mirror element may be the same. Although the rear window 40 of the car has been described as an example, a similar element may be arranged on a window of a building or the like. In that case, the color of the light source 42 may be neutral white or a light bulb color.
(Example 3)
The case where the light emitting device is applied to general lighting such as lighting in a long corridor will be described. FIG. 7A is a cross-sectional view illustrating a configuration of a lighting device with a simple structure and high functionality and low power consumption. FIG. 7B is a cross-sectional view showing the pedestrian lighting operation of the lighting device of FIG. 7A.

  The configuration of the illumination device in FIG. 7A is basically the same as that of the light emitting device in FIG. 3A. In addition, the thickness of the cell of the mirror element 43 produced as an example was 500 microns. As the electrode on the substrate, a solid electrode not finely patterned was used.

  For example, a white light source is used as the light source 42. A human sensor S is installed in the vicinity of each mirror element and mirror, and the presence or absence of a person or the like can be detected. For example, when a person is walking under the second mirror element 43b, the corresponding second person sensor S2 detects the appearance, turns on the light source 42, and voltage between the opposing transparent electrodes 12, 22 of the second mirror element 43b. Is applied to obtain a reflective state. As shown in FIG. 7B, the illumination device can reflect light by the second mirror element 43b and illuminate only the vicinity of the person's position.

If a person moves, the mirror element that is in a reflecting state is changed accordingly. In this way, a highly functional and low power consumption lighting device can be realized with a very simple structure.
(Modification)
It is also possible to use a cell structure of the mirror element 43 with a microprism formed on the microprism 13 in which one transparent electrode of the mirror element 43 is formed on a transparent substrate.

  FIG. 8A is a perspective view showing the microprism 13 formed on the first transparent substrate 11. Hereinafter, a manufacturing process of forming the transparent electrode 12 on the surface of the microprism 13 and the microprism 13 on the transparent substrate 11 will be described.

  As shown in FIGS. 8B to 8F, the microprism 13 is formed on the first transparent substrate 11. The shape of the microprism 13 is, for example, a cross-sectional pitch of 20 microns, a height of 5 microns, a vertex angle of about 75 degrees, and a base angle of 15 degrees and 90 degrees, and has a slit shape when viewed from above.

  As shown in FIG. 8B, a first transparent substrate 11 is prepared. As shown in FIG. 8C, a predetermined amount of acrylic UV curable resin 13 a is dropped on the first transparent substrate 11. As shown in FIG. 8D, a mold 19 having the shape of the microprism 13 is placed on a resin 13a at a predetermined position, and a thick quartz 18 or the like is placed on the back side of the first transparent substrate 11 to be reinforced. Press. As shown in FIG. 8E, after being pressed for 1 minute or longer, the UV curable resin 13a is sufficiently spread and then irradiated with ultraviolet rays from the first transparent substrate 11 side to cure the UV curable resin 13a. For example, the irradiation amount is 20 J / cm 2, but the irradiation amount is not so important because the resin 13a only needs to be cured.

  The first transparent substrate 11 on which the microprism 13 is formed is cleaned by a cleaning machine. The cleaning method was performed in the order of brush cleaning using an alkaline detergent, pure water cleaning, air blow, ultraviolet (UV) irradiation, and infrared (IR) drying, but the cleaning method is not limited to this. High pressure spray cleaning or plasma cleaning may be performed.

  As shown in FIG. 8F, a first transparent electrode 12 using an ITO film is formed on the surface of the microprism 13 by magnetron sputtering. The ITO film may be patterned using a SUS mask having holes in a predetermined shape. After forming the ITO film, patterning may be performed by a photolithography process.

  A second transparent substrate 21 on which a second transparent electrode 22 such as ITO is formed is prepared. The second transparent electrode 22 is a transparent electrode formed by sputtering, CVD, vapor deposition, or the like, and is a smooth electrode film formed on a flat substrate surface.

  A mirror element is formed in which a substrate on which a transparent electrode is formed on a microprism and a substrate on which a transparent electrode is formed on a flat surface are opposed to each other. As an example, a cell having a cell thickness of 500 microns was produced. As the flat transparent electrode, a solid electrode not finely patterned was used. The mirror element with microprism 43 shown in FIG.

  As shown in FIG. 8H, a cell structure is produced in the same manufacturing process using a metal electrode 32 such as aluminum or silver instead of the second transparent electrode 22 and is installed on the optical axis where the mirror element 43 is arranged. It is good also as a micro prism reflecting plate with a metal electrode (refer FIG.3,4,5).

  FIG. 8I shows a microprism electrode side in which a DC voltage is applied between the first and second transparent electrodes 12 and 22 of the mirror element 43 with a microprism using the first transparent electrode 12 as a negative electrode from a DC power supply 15. It is sectional drawing which shows the mirror element 43 in the state in which the silver thin film 7 deposited.

  FIG. 8J is a cross-sectional view showing the reflection direction when light is incident on the silver thin film 7 on the microprism electrode of the mirror element indicated by 8I from above the normal direction of the substrate. Incident light traveling downward from above becomes reflected light that is reflected obliquely upward to the right.

  In this way, by using the microprism, it is possible to improve the degree of freedom of the direction of reflected light with respect to the installation position of the mirror element 43.

  Further, it is also possible to selectively use the second transparent electrode 22 that faces the other as the reflecting surface.

  FIG. 8K shows a flat surface in which a DC voltage having the second transparent electrode 22 as a negative electrode is applied from the DC power source 15 between the first and second transparent electrodes 12 and 22 of the mirror element 43 with microprism. 3 is a cross-sectional view showing a mirror element 43 in a state where a silver thin film 7 is deposited on a transparent electrode 22. FIG.

  FIG. 8L is a cross section showing a state where light is incident on the silver thin film 7 formed on the flat surface of the mirror element indicated by 8K from the substrate normal direction of the mirror element and reflected by the silver thin film 7 on the flat surface. In the figure, incident light is reflected in the normal direction (reverse direction).

  The mirror element with microprism 43 can set the reflection direction of reflected light to one of two directions by changing the polarity of the DC voltage to be applied.

  FIG. 8M is a cross-sectional view showing a general illumination device in which mirror elements 43a, 43b, 43c, 43d with microprisms and a microprism reflector plate 48 with metal electrodes are arranged on the optical axis. The direction in which each mirror element and the microprism reflector 48 can reflect is shown in FIG. 8N. The mirror elements 43a, 43b, 43c, and 43d with microprisms switch the polarity of the voltage applied between the transparent electrodes, whereby the direction 61 of the reflected light by the mirror on the microprism electrode and the reflected light by the mirror on the flat surface Direction 60 can be selected. Similarly, the microprism reflecting plate 48 is set to either the direction 61 of reflected light by the mirror on the microprism electrode or the direction 62 of reflected light by the metal mirror on the flat surface. Each mirror element and reflector can emit light in two directions. Therefore, light can be irradiated in more directions.

  The second transparent electrode 22 is provided as a flat electrode. However, the present invention is not limited to this, and a microprism different from the first transparent electrode 12 may be provided. If the opposing surface of the second transparent substrate is formed in a different shape so as to reflect in a direction different from that of the first transparent electrode 12 when the silver thin film is deposited, the direction of the reflected light is changed by switching the voltage. Can do.

  Note that the configuration of the lighting device is not limited to these. For example, a lens, a prism, an enlargement / reduction reflector, or the like may be installed in the illumination device.

  It will be apparent to those skilled in the art that various other changes, substitutions, improvements, combinations, and the like are possible.

Claims (8)

A light source that emits light on the optical axis;
And at least one mirror element arranged to be inclined with respect to the optical axis,
The mirror element is
First and second transparent substrates arranged opposite to each other;
First and second transparent electrodes formed above the opposing surfaces of the first and second transparent substrates;
An electrolytic solution that is disposed between the first and second transparent electrodes and includes an electrodeposition material containing metal ions;
Including
A control circuit for applying a voltage between the first and second transparent electrodes of the mirror element;
A light emitting device. The number of the mirror elements is two or more, and the inclination angle with respect to the optical axis of the light source is the same angle.
The light emitting device according to claim 1. The number of the mirror elements is two or more, and the inclination angle with respect to the optical axis of the light source is different for each of the mirror elements.
The light emitting device according to claim 1.   4. The light emitting device according to claim 1, further comprising a reflecting plate on an extension line of the optical axis on which the mirror element is disposed. 5. In at least one of the mirror elements, including a microprism formed on an opposing surface of the first transparent substrate,
5. The light emitting device according to claim 1, wherein the first transparent electrode is formed on a surface of the microprism. The opposing surface of the second transparent substrate is formed in a surface shape different from the opposing surface of the first transparent substrate,
The light emitting device according to claim 5, wherein the control circuit has a function of switching a polarity to be applied.   The first and second transparent electrodes have at least one transparent electrode having two or more electrode patterns, and the control circuit has a function of separately applying a voltage to each electrode pattern. The light emitting device according to claim 1. A light source container that can accommodate a light source that emits a light beam on the optical axis;
And at least one mirror element arranged to be inclined with respect to the optical axis,
The mirror element is
First and second transparent substrates arranged opposite to each other;
First and second transparent electrodes formed above the opposing surfaces of the first and second transparent substrates;
An electrolyte containing an electrodeposition material containing metal ions disposed between the first and second transparent electrodes;
Including
A control circuit for applying a voltage between the first and second transparent electrodes of the mirror element;
A light emitting device.