Lighting device

Abstract

A lighting device according to the present invention which includes an optical element drive circuit unit (60) that generates a signal for driving a first liquid crystal cell included in an optical element, and a first push switch (61) that includes a push button to be operated by a user and is connected to the optical element drive circuit unit (60), wherein: the optical element drive circuit unit (60) generates a first signal (S1) having a first pulse wave (PW1) and a second signal (S2) having a second pulse wave (PW2) obtained by inverting the phase of the first pulse wave (PW1); the first signal (S1) is inputted to the optical element such that the first pulse wave (PW1) is applied to a first transparent electrode; the second signal (S2) is inputted to the optical element such that the second pulse wave (PW2) is applied to a second transparent electrode; one of the plurality of input-side contacts electrically connected to the output-side contact is selected each time the push button (61) of the first push switch (61) is pressed; and the amplitudes of the first pulse wave (PW1) and the second pulse wave (PW2) each change in a stepwise manner.

Description

Technical Field

[0001] One embodiment of the present invention relates to a lighting device that uses liquid crystal and controls the light distribution of light emitted from a light source.

Background Art

[0002] Conventionally, an optical element, so-called a liquid crystal lens, that adjusts the voltage applied to a liquid crystal and utilizes the change in the refractive index of the liquid crystal is known. In addition, the development of a lighting device using a light source and a liquid crystal lens has been underway (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a lighting device including an optical element such as a liquid crystal lens, the spread of light emitted from the lighting device, that is, the light distribution angle can be adjusted by the optical element. In such a lighting device, not only when the lighting device is installed and used at a predetermined position, but also when the user carries and uses it. When the user uses the lighting device while holding it, it is preferable that the adjustment of the light distribution angle can be easily performed in the state where the user holds the lighting device.

[0005] One object of one embodiment of the present invention is to provide a lighting device capable of easily adjusting the light distribution angle. Another object of one embodiment of the present invention is to provide a lighting device capable of easily adjusting the light distribution shape.

Means for Solving the Problems

[0006] An illumination device according to one embodiment of the present invention includes a light source, an optical element including a first liquid crystal cell that diffusely transmits light emitted from the light source, an optical element driving circuit unit connected to the optical element and generating a signal for driving the optical element, and a first push switch including a push button operated by a user and connected to the optical element driving circuit unit, wherein the first liquid crystal cell includes a first substrate on which first transparent electrodes and second transparent electrodes extending in a first direction are alternately provided, a second substrate on which third transparent electrodes and fourth transparent electrodes extending in a second direction intersecting the first direction are alternately provided, and a liquid crystal layer between the first substrate and the second substrate, and the optical element driving circuit unit is electrically connected to a plurality of input-side contacts of the first push switch. The optical element includes a first resistor voltage divider circuit, a first output terminal electrically connected to the output contact of a first push switch and outputting a first signal having a first pulse wave, and a second output terminal electrically connected to the output contact of the first push switch and outputting a second signal having a second pulse wave inverted in phase of the first pulse wave, wherein the first signal is input to the optical element so that the first pulse wave is applied to a first transparent electrode, and the second signal is input to the optical element so that the second pulse wave is applied to a second transparent electrode, and each time the push button of the first push switch is pressed one of a plurality of input contacts electrically connected to the output contact is selected and the amplitudes of the first pulse wave and the second pulse wave are changed in steps.

[0007] An illumination device according to one embodiment of the present invention includes a light source, an optical element including a first liquid crystal cell that diffusely transmits light emitted from the light source, an optical element driving circuit unit connected to the optical element and generating a signal for driving the optical element, a first push switch including a first push button operated by the user and connected to the optical element driving circuit unit, and a second push switch including a second push button operated by the user, the first input side contact, second input side contact, third input side contact, and fourth input side contact being electrically connected to the optical element driving circuit unit, and the first output side contact and second output side contact being electrically connected to the optical element, wherein the first liquid crystal cell includes a first substrate on which first transparent electrodes and second transparent electrodes extending in a first direction are alternately provided, a second substrate on which third transparent electrodes and fourth transparent electrodes extending in a second direction intersecting the first direction are alternately provided, and the first substrate and the second The optical element driving circuit includes a liquid crystal layer between the substrate and the optical element, and generates a first signal having a first pulse wave, a second signal having the phase of the first pulse wave inverted, and a third signal having a fixed potential. The first signal and the second signal are input to the first input contact and the second input contact of the second push switch, respectively, and the third signal is input to the third input contact and the fourth input contact of the second push switch. Each time the second push button of the second push switch is pressed, one of the first input contact and the second input contact that is electrically connected to the first output contact is selected, and one of the third input contact and the fourth input contact that is electrically connected to the second output contact is selected, and the first pulse wave and the second pulse wave are applied to the first transparent electrode and the second transparent electrode, respectively, or a fixed potential is applied to the first transparent electrode and the second transparent electrode. [Brief explanation of the drawing]

[0008] [Figure 1A] This is a schematic side view showing the configuration of a lighting device relating to one embodiment of the present invention. [Figure 1B] This is a schematic top view showing the configuration of a lighting device relating to one embodiment of the present invention. [Figure 1C]This is a schematic block diagram showing the internal configuration of a lighting device according to one embodiment of the present invention. [Figure 2A] This is a schematic cross-sectional view showing the configuration of the optical elements of a lighting device according to one embodiment of the present invention. [Figure 2B] This is a schematic cross-sectional view showing the configuration of the optical elements of a lighting device according to one embodiment of the present invention. [Figure 3A] This is a schematic plan view showing the electrode pattern of a liquid crystal cell included in the optical element of a lighting device according to one embodiment of the present invention. [Figure 3B] This is a schematic plan view showing the electrode pattern of a liquid crystal cell included in the optical element of a lighting device according to one embodiment of the present invention. [Figure 4A] This is a schematic diagram illustrating the optical properties of a liquid crystal cell included in the optical element of a lighting device according to one embodiment of the present invention. [Figure 4B] This is a schematic diagram illustrating the optical properties of a liquid crystal cell included in the optical element of a lighting device according to one embodiment of the present invention. [Figure 5] This is a block diagram showing the circuit configuration of the optical element drive circuit section of a lighting device according to one embodiment of the present invention. [Figure 6] This is a circuit diagram showing the circuit configuration of a push switch and a resistive voltage divider circuit included in the optical element driving circuit section of a lighting device according to one embodiment of the present invention. [Figure 7] This is a schematic diagram showing the signals input to the optical elements of a lighting device according to one embodiment of the present invention. [Figure 8] This is a block diagram showing the circuit configuration of the optical element drive circuit section of a lighting device according to one embodiment of the present invention. [Figure 9] This is a block diagram showing the circuit configuration of the optical element drive circuit section of a lighting device according to one embodiment of the present invention. [Figure 10] This is a schematic block diagram showing the internal configuration of a lighting device according to one embodiment of the present invention. [Figure 11] This is a schematic diagram showing the signals input to the optical elements of a lighting device according to one embodiment of the present invention. [Modes for carrying out the invention]

[0009] Hereinafter, each embodiment of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various forms without departing from the gist of its technical idea, and is not to be construed as being limited to the description of the embodiments illustrated below.

[0010] For the sake of clearer explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual aspect, but this is merely an example, and the illustrated shape itself does not limit the interpretation of the present invention. Also, in the drawings, components having the same functions as those already described with respect to the figures appearing in the specification may be given the same reference numerals even in different figures, and redundant explanations may be omitted.

[0011] When a single film is processed to form a plurality of structures, each structure may have different functions and roles, and each structure may also have a different substrate on which it is formed. However, these plurality of structures are derived from a film formed as the same layer in the same process and have the same material. Therefore, these plurality of films are defined as existing in the same layer.

[0012] In expressing the aspect of arranging another structure on a certain structure, when simply denoted as "above", unless otherwise specified, it includes both the case of arranging another structure directly above and in contact with a certain structure, and the case of arranging another structure above a certain structure through yet another structure.

[0013] <First Embodiment> Referring to FIGS. 1A to 7, a lighting device 1 according to an embodiment of the present invention will be described.

[0014] [1. Configuration of Lighting Device 1] FIGS. 1A and 1B are respectively schematic side views and top views showing the configuration of a lighting device 1 according to an embodiment of the present invention.

[0015] As shown in Figures 1A and 1B, the lighting device 1 includes a main body 1a and a lighting unit 1b. The lighting unit 1b is connected to the end of the main body 1a. The main body 1a has a cylindrical shape, and light is emitted from the lighting unit 1b. The user can hold the main body 1a and illuminate their surroundings with the light emitted from the lighting unit 1b. In this way, the lighting device 1 can be used as a flashlight. However, the uses of the lighting device 1 are not limited to this. The lighting device 1 can also be used as a spotlight.

[0016] For the sake of clarity, in the following explanation, the direction in which the main body 1a extends in a top view is defined as the z-axis direction. That is, the direction of light emission from the illumination unit 1b is the z-axis direction. Also, in a top view, the direction perpendicular to the z-axis direction is defined as the x-axis direction. That is, the diffusion direction of light emitted from the illumination unit 1b is the x-axis direction. Furthermore, the direction perpendicular to both the z-axis and x-axis directions is defined as the y-axis direction.

[0017] In a side view, the main body 1a has a curved shape. Specifically, the main body 1a has a shape in which a portion extending parallel to the z-axis direction and connected to the illumination unit 1b is joined to a portion extending in a direction not parallel to the z-axis direction. With the main body 1a having such a shape, even when the user uses the illumination device 1 close to their face, the user can grip the main body 1a without putting excessive force on their wrist and illuminate the area around them. However, the shape of the main body 1a is not limited to this. The shape of the main body 1a can be determined according to the manner in which the illumination device 1 is used.

[0018] A push button for a push switch 61 is provided on the top surface of the main body 1a. The push switch 61 adjusts the beam angle of the light emitted from the lighting unit 1b. That is, when the user presses the push button for the push switch 61, the beam angle of the light emitted from the lighting unit 1b changes in steps. The main body 1a also includes a light source adjustment switch 71 for adjusting the brightness of the light emitted from the lighting unit 1b. The side of the main body 1a may be provided with a knob for a slide switch or a push button for a push switch. When the light source adjustment switch 71 is a slide switch, the brightness of the light emitted from the lighting unit 1b can be continuously adjusted by sliding the knob. On the other hand, when the light source adjustment switch 71 is a push switch, the brightness of the light emitted from the lighting unit 1b can be adjusted in steps by pressing the push button of the push switch.

[0019] Figure 1C is a schematic block diagram showing the internal configuration of a lighting device 1 according to one embodiment of the present invention.

[0020] As shown in Figure 1C, the lighting device 1 includes an optical element 10, a light source 20, an optical adjustment unit 30, a battery 40, a charging module 50, an optical element drive circuit unit 60, and a light source drive circuit unit 70. The optical element 10, the light source 20, and the optical adjustment unit 30 are housed in the lighting unit 1b. The battery 40, the charging module 50, the optical element drive circuit unit 60, and the light source drive circuit unit 70 are housed in the main body unit 1a.

[0021] Figure 1C shows the connections of each component. The optical element drive circuit 60 is connected to the optical element 10 and the battery 40. Power is supplied to the optical element drive circuit 60 from the battery 40, and the optical element drive circuit 60 generates a signal to drive the optical element 10. The optical element drive circuit 60 is also connected to the push switch 61. The light source drive circuit 70 is connected to the light source 20 and the battery 40. Power is supplied to the light source drive circuit 70 from the battery 40, and the light source drive circuit 70 generates a signal to drive the light source 20. The light source drive circuit 70 is also connected to the light source adjustment switch 71.

[0022] The battery 40 is connected to the charging module 50. The battery 40 can be a so-called secondary battery (e.g., a lithium-ion battery) that can be used repeatedly by recharging. The battery 40 can be charged via the charging module 50. The charging module 50 controls the charging of the battery 40 while preventing overcharging. Charging of the battery 40 may be done via a wired connection or a wireless connection. In the wired connection, the charging module 50 is provided with terminals for connecting a power cable, and power is charged to the battery 40 via the power cable connected to the terminals of the charging module 50. In the wireless connection, the charging module 50 is provided with a power receiving coil, and the power converted by the power receiving coil is charged to the battery 40. Note that the lighting device 1 can also be configured without a charging module 50. In this case, the battery 40 can be a so-called primary battery (e.g., an alkaline battery or a manganese battery) that cannot be recharged.

[0023] The light source 20 emits light to the optical element 10. For example, a light-emitting diode (LED) can be used as the light source 20. Multiple LEDs may be used as the light source 20. When multiple LEDs are used as the light source 20, LEDs of the same color may be used, or LEDs of different colors may be used. Note that the light source 20 is not limited to LEDs. The light source 20 can be any element or device capable of emitting light.

[0024] The optical adjustment unit 30 is positioned between the optical element 10 and the light source 20, and focuses, diffuses, or reflects the light emitted from the light source 20. For example, the optical adjustment unit 30 is an optical component consisting of a lens, a reflector, or a combination thereof.

[0025] [2. Configuration of the optical element 10] Now, with reference to Figures 2A to 4B, the configuration of the optical element 10 will be explained.

[0026] [2-1. Structure of the optical element 10] Figures 2A and 2B are schematic cross-sectional views showing the configuration of an optical element 10 of a lighting device 1 according to one embodiment of the present invention. Figure 2A is a cross-sectional view of the optical element 10 cut by a plane perpendicular to the y-axis direction, and Figure 2B is a cross-sectional view of the optical element 10 cut by a plane perpendicular to the x-axis direction.

[0027] The optical element 10 includes four liquid crystal cells 100 (a first liquid crystal cell 100-1, a second liquid crystal cell 100-2, a third liquid crystal cell 100-3, and a fourth liquid crystal cell 100-4). In the optical element 10, the first liquid crystal cell 100-1, the second liquid crystal cell 100-2, the third liquid crystal cell 100-3, and the fourth liquid crystal cell 100-4 are stacked sequentially in the z-axis direction, starting from the side closest to the light source 20. Light emitted from the light source 20 is incident on the first liquid crystal cell 100-1 and emitted from the fourth liquid crystal cell 100-4. In the lighting device 1, the diffusion and polarization of light are controlled by the four liquid crystal cells 100 included in the optical element 10, and the light distribution of the light emitted from the fourth liquid crystal cell 100-4 can be changed. That is, the optical element 10 can diffusely transmit the light emitted from the light source 20 and control the light distribution.

[0028] Figures 2A and 2B show the configuration of an optical element 10 containing four liquid crystal cells 100, but the number of liquid crystal cells 100 in the optical element 10 is not limited to four. The optical element 10 only needs to contain at least one liquid crystal cell 100.

[0029] As shown in Figures 2A and 2B, each of the first liquid crystal cells 100-1 to the fourth liquid crystal cells 100-4 includes a first substrate 110-1, a second substrate 110-2, a plurality of first transparent electrodes 120-1, a plurality of second transparent electrodes 120-2, a plurality of third transparent electrodes 120-3, a plurality of fourth transparent electrodes 120-4, a first alignment film 130-1, a second alignment film 130-2, a sealing material 140, and a liquid crystal layer 150. The first transparent electrodes 120-1 and the second transparent electrodes 120-2 are arranged alternately on the first substrate 110-1. In addition, the first alignment film 130-1 is provided on the first substrate 110-1 so as to cover the first transparent electrodes 120-1 and the second transparent electrodes 120-2. On the second substrate 110-2, a third transparent electrode 120-3 and a fourth transparent electrode 120-4 are arranged alternately. Furthermore, a second alignment film 130-2 is provided on the second substrate 110-2 so as to cover the third transparent electrode 120-3 and the fourth transparent electrode 120-4. The first substrate 110-1 and the second substrate 110-2 are arranged so that the first transparent electrode 120-1 and the second transparent electrode 120-2 face the third transparent electrode 120-3 and the fourth transparent electrode 120-4, and are bonded together via a sealing material 140 provided around the periphery of the first substrate 110-1 and the second substrate 110-2. Liquid crystal is sealed in the space surrounded by the first substrate 110-1 (more specifically, the first alignment film 130-1), the second substrate 110-2 (more specifically, the second alignment film 130-2), and the sealing material 140, and a liquid crystal layer 150 is provided between the first substrate 110-1 and the second substrate 110-2.

[0030] An optically elastic resin layer 160 is provided between the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2. Similarly, an optically elastic resin layer 160 is provided between the second liquid crystal cell 100-2 and the third liquid crystal cell 100-3, and between the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4. As the optically elastic resin layer 160, for example, an adhesive containing a light-transmitting acrylic resin can be used. That is, the optically elastic resin layer 160 can bond and fix two adjacent liquid crystal cells 100 together.

[0031] For each of the first substrate 110-1 and the second substrate 110-2, a translucent rigid substrate such as a glass substrate, a quartz substrate, or a sapphire substrate can be used. Alternatively, for each of the first substrate 110-1 and the second substrate 110-2, a translucent flexible substrate such as a polyimide resin substrate, an acrylic resin substrate, a siloxane resin substrate, or a fluororesin substrate can also be used.

[0032] Each of the first transparent electrode 120-1, the second transparent electrode 120-2, the third transparent electrode 120-3, and the fourth transparent electrode 120-4 functions as an electrode for forming an electric field in the liquid crystal layer 150. Transparent conductive materials such as indium tin oxide (ITO) or indium zinc oxide (IZO) are used as each of the first transparent electrode 120-1, the second transparent electrode 120-2, the third transparent electrode 120-3, and the fourth transparent electrode 120-4.

[0033] In the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2, the first transparent electrode 120-1 and the second transparent electrode 120-2 extend in the x-axis direction, and the third transparent electrode 120-3 and the fourth transparent electrode 120-4 extend in the y-axis direction. Similarly, in the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4, the first transparent electrode 120-1 and the second transparent electrode 120-2 extend in the y-axis direction, and the third transparent electrode 120-3 and the fourth transparent electrode 120-4 extend in the x-axis direction.

[0034] In the following, unless otherwise specified, the first transparent electrode 120-1 to the fourth transparent electrode 120-4 may be referred to simply as transparent electrode 120.

[0035] Each of the first alignment film 130-1 and the second alignment film 130-2 aligns the liquid crystal molecules in the liquid crystal layer 150 in a predetermined direction. Polyimide resin or the like can be used as each of the first alignment film 130-1 and the second alignment film 130-2. The first alignment film 130-1 and the second alignment film 130-2 may also be given alignment characteristics by an alignment treatment such as the rubbing method or the photo-alignment method. The rubbing method involves rubbing the surface of the alignment film in one direction. The photo-alignment method involves irradiating the alignment film with linearly polarized ultraviolet light.

[0036] The first alignment film 130-1 is oriented so that the liquid crystal molecules on the first substrate 110-1 side of the liquid crystal layer 150 are aligned in a direction perpendicular to the extending direction of the first transparent electrode 120-1 and the second transparent electrode 120-2. Similarly, the second alignment film 130-2 is oriented so that the liquid crystal molecules on the second substrate 110-2 side of the liquid crystal layer 150 are aligned in a direction perpendicular to the extending direction of the third transparent electrode 120-3 and the fourth transparent electrode 120-4. As a result, in the first liquid crystal cell 100-1 and the second liquid crystal cell 100-2, the long axis of the liquid crystal molecules on the first substrate 110-1 side is oriented in the y-axis direction, and the long axis of the liquid crystal molecules on the second substrate 110-2 side is oriented in the x-axis direction. Furthermore, in the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4, the long axis of the liquid crystal molecules on the first substrate 110-1 side is oriented in the x-axis direction, and the long axis of the liquid crystal molecules on the second substrate 110-2 side is oriented in the y-axis direction.

[0037] As the sealing material 140, an adhesive containing epoxy resin or acrylic resin is used. The adhesive may be UV-curing or thermosetting.

[0038] The liquid crystal layer 150 can refract transmitted light or change the polarization state of transmitted light depending on the orientation of the liquid crystal molecules. Nematic liquid crystals are used as the liquid crystal of the liquid crystal layer 150. The liquid crystal described in this embodiment is positive type, but a negative type configuration can also be applied by changing the orientation direction of the liquid crystal molecules when no voltage is applied to the transparent electrode 120. Furthermore, it is preferable that the liquid crystal contains a chiral agent that imparts a twist to the liquid crystal molecules.

[0039] [2-2. Electrode Pattern of Liquid Crystal Cell 100] Figures 3A and 3B are schematic plan views showing the electrode patterns of liquid crystal cells 100 included in the optical element 10 of a lighting device 1 according to one embodiment of the present invention. Specifically, Figure 3A is a plan view showing the electrode pattern formed on the first substrate 110-1 of the first liquid crystal cell 100-1, and Figure 3B is a plan view showing the electrode pattern formed on the second substrate 110-2 of the first liquid crystal cell 100-1.

[0040] As shown in Figure 3A, a first connection pad 121-1 and a second connection pad 121-2 are provided on the first substrate 110-1. Multiple first transparent electrodes 120-1 are electrically connected to the first connection pad 121-1. Multiple second transparent electrodes 120-2 are electrically connected to the second connection pad 121-2. As described above, a first alignment film 130-1 is provided on the multiple first transparent electrodes 120-1 and the multiple second transparent electrodes 120-2 (not shown in Figure 3A). The first alignment film 130-1 has undergone an alignment process, and the orientation direction of the first alignment film 130-1 is in the y-axis direction.

[0041] As shown in Figure 3B, the second substrate 110-2 is provided with a third connection pad 121-3, a fourth connection pad 121-4, a first terminal 122-1, a second terminal 122-2, a third terminal 122-3, and a fourth terminal 122-4. Multiple third transparent electrodes 120-3 are electrically connected to the third terminal 122-3. Multiple fourth transparent electrodes 120-4 are electrically connected to the fourth terminal 122-4. In addition, the third connection pad 121-3 is electrically connected to the first terminal 122-1. The fourth connection pad 121-4 is electrically connected to the second terminal 122-2. As described above, a second alignment film 130-2 is provided on the multiple third transparent electrodes 120-3 and the multiple fourth transparent electrodes 120-4 (not shown in Figure 3B). The second orientation film 130-2 has undergone orientation treatment, and the orientation direction of the first orientation film 130-1 is in the x-axis direction.

[0042] When the first substrate 110-1 and the second substrate 110-2 are bonded together, the first connection pad 121-1 and the second connection pad 121-2 overlap with the third connection pad 121-3 and the fourth connection pad 121-4, respectively. A conductive electrode is provided between the first connection pad 121-1 and the third connection pad 121-3, and the first connection pad 121-1 and the third connection pad 121-3 are electrically connected via the conductive electrode. Similarly, a conductive electrode is provided between the second connection pad 121-2 and the fourth connection pad 121-4, and the second connection pad 121-2 and the fourth connection pad 121-4 are electrically connected via the conductive electrode. Therefore, the first transparent electrode 120-1 and the second transparent electrode 120-2 on the first substrate 110-1 are electrically connected to the first terminal 122-1 and the second terminal 122-2, respectively.

[0043] The electrode pattern of the second liquid crystal cell 100-2 is identical to that of the first liquid crystal cell 100-1. The electrode pattern configurations of the third liquid crystal cell 100-3 and the fourth liquid crystal cell 100-4 are the same as those of the first liquid crystal cell 100-1, except that the extension direction of the transparent electrode 120 differs by 90°.

[0044] In the liquid crystal cell 100, the first terminals 122-1 to the fourth terminals 122-4 on the second substrate 110-2 are exposed from the first substrate 110-1. In each of the first liquid crystal cells 100-1 to the fourth liquid crystal cells 100-4, the exposed first terminals 122-1 to the fourth terminals 122-4 are electrically connected to the optical element driving circuit 60. As will be described in detail later, a signal generated in the optical element driving circuit 60 is input to the first terminals 122-1 to the fourth terminals 122-4 of each of the first liquid crystal cells 100-1 to the fourth liquid crystal cells 100-4, thereby applying a predetermined potential to each of the first transparent electrodes 120-1 to the fourth transparent electrodes 120-4 of each of the first liquid crystal cells 100-1 to the fourth liquid crystal cells 100-4. This changes the orientation of the liquid crystal molecules in the liquid crystal layer 150 of each of the first liquid crystal cell 100-1 to the fourth liquid crystal cell 100-4, thereby changing the light distribution of the light transmitted through the optical element 10.

[0045] [2-3. Optical characteristics of liquid crystal cell 100] Figures 4A and 4B are schematic diagrams illustrating the optical characteristics of a liquid crystal cell 100 included in the optical element 10 of a lighting device 1 according to one embodiment of the present invention. Specifically, Figure 4A shows the liquid crystal cell 100 when no voltage is applied to the transparent electrode 120, and Figure 4B shows the liquid crystal cell 100 when a voltage is applied to the transparent electrode 120.

[0046] As shown in Figure 4A, the liquid crystal molecules on the first substrate 110-1 side of the liquid crystal layer 150 are oriented in the y-axis direction, and the liquid crystal molecules on the second substrate 110-2 side of the liquid crystal layer 150 are oriented in the x-axis direction. Therefore, when no voltage is applied to any of the first transparent electrodes 120-1 to the fourth transparent electrodes 120-4, the liquid crystal molecules in the liquid crystal layer 150 are oriented so as they twist 90° from the first substrate 110-1 toward the second substrate 110-2. In addition, the plane of polarization (the direction of the polarization axis or polarization component) of light transmitted through the liquid crystal layer 150 is rotated 90° according to the orientation direction of the liquid crystal molecules. That is, the light transmitted through the liquid crystal layer 150 (more specifically, the polarization component of the light transmitted through the liquid crystal layer 150) rotates.

[0047] On the other hand, when a voltage is applied such that a potential difference is created between two adjacent transparent electrodes 120, an electric field (hereinafter referred to as a "transverse electric field") is generated between the two adjacent transparent electrodes 120, and the orientation of the liquid crystal molecules changes. As shown in Figure 4B, the liquid crystal molecules in the liquid crystal layer 150 are oriented so as they twist by 90° from the first substrate 110-1 toward the second substrate 110-2. The liquid crystal molecules near the first substrate 110-1 are arranged in a convex arc shape relative to the first substrate 110-1 due to the transverse electric field between the first transparent electrode 120-1 and the second transparent electrode 120-2, and the liquid crystal molecules near the second substrate 110-2 are arranged in a convex arc shape relative to the second substrate 110-2 due to the transverse electric field between the third transparent electrode 120-3 and the fourth transparent electrode 120-4. The liquid crystal molecules arranged in a convex arc shape have a refractive index distribution, and the polarization component of light along the orientation direction of the liquid crystal molecules is diffused. Furthermore, since the cell gap d, which is the distance between the first substrate 110-1 and the second substrate 110-2, is sufficiently larger than the distance between two adjacent transparent electrodes 120 (for example, 8 μm ≤ d ≤ 50 μm, preferably 10 μm ≤ d ≤ 30 μm, and even more preferably 15 μm ≤ d ≤ 25 μm), the electric field formed between the transparent electrodes 120 does not significantly affect the liquid crystal molecules located near the center between the first substrate 110-1 and the second substrate 110-2.

[0048] The light emitted from the light source 20 contains a polarization component in the x-axis direction (hereinafter referred to as the "P-polarization component") and a polarization component in the y-axis direction (hereinafter referred to as the "S-polarization component"). However, for convenience, the light incident on the liquid crystal cell 100 will be described below as being divided into a first light 1000-1 having a P-polarization component and a second light 1000-2 having an S-polarization component.

[0049] The P-polarized component of the first light 1000-1 incident from the first substrate 110-1 to the liquid crystal layer 150 is different from the orientation direction of the liquid crystal molecules on the first substrate 110-1 side, so the first light 1000-1 is not diffused (see (1) in Figure 4B). Also, the first light 1000-1 rotates as it passes through the liquid crystal layer 150, and its polarization component changes from a P-polarized component to an S-polarized component. The S-polarized component of the first light 1000-1 is different from the orientation direction of the liquid crystal molecules on the second substrate 110-2 side, so the first light 1000-1 is not diffused (see (2) in Figure 4B).

[0050] The S-polarized component of the second light 1000-2 incident from the first substrate 110-1 to the liquid crystal layer 150 is the same as the orientation direction of the liquid crystal molecules on the first substrate 110-1 side. Therefore, the second light 1000-2 is diffused in the y-axis direction according to the refractive index distribution of the liquid crystal molecules (see (3) in Figure 4B). In addition, the second light 1000-2 rotates as it passes through the liquid crystal layer 150, and its polarization component changes from an S-polarized component to a P-polarized component. The P-polarized component of the second light 1000-2 is the same as the orientation direction of the liquid crystal molecules on the second substrate 110-2 side. Therefore, the second light 1000-2 is diffused in the x-axis direction according to the refractive index distribution of the liquid crystal molecules (see (4) in Figure 4B).

[0051] The above description concerns the configuration of a single liquid crystal cell 100. However, in an optical element 10 containing multiple liquid crystal cells 100, the P-polarization component or S-polarization component of the light incident on the optical element 10 is controlled by each of the multiple liquid crystal cells 100.

[0052] [3. Configuration of the optical element driving circuit section 60] Figure 5 is a block diagram showing the circuit configuration of the optical element driving circuit section 60 of the lighting device 1 according to one embodiment of the present invention. Note that Figure 5 is an example of the circuit configuration of the optical element driving circuit section 60, and the circuit configuration of the optical element driving circuit section 60 is not limited to this. Also, in Figure 5, some components that can be understood by those skilled in the art may be omitted.

[0053] As shown in Figure 5, the optical element driving circuit 60 includes a push switch 61, a resistor voltage divider circuit 66, a first transistor Tr1, a second transistor Tr2, a third transistor Tr3, and an oscillator OSC. The optical element driving circuit 60 is supplied with potential from the battery 40. The potential output from the battery 40 is, for example, 15V, but is not limited to this. However, for convenience, the following explanation will assume that the output potential of the battery 40 is 15V.

[0054] The resistive voltage divider circuit 66 is electrically connected to the battery 40. The resistive voltage divider circuit 66 is also electrically connected to the push switch 61. The resistive voltage divider circuit 66 divides the 15V potential supplied by the battery 40 in steps, generating multiple potentials. The push switch 61 selects and outputs one of the multiple potentials generated by the resistive voltage divider circuit 66. The circuit configuration of the push switch 61 and the resistive voltage divider circuit 66 will now be described with reference to Figure 6.

[0055] Figure 6 is a circuit diagram showing the circuit configuration of a push switch 61 and a resistive voltage divider circuit 66 included in the optical element driving circuit section 60 of a lighting device 1 according to one embodiment of the present invention.

[0056] The resistor voltage divider circuit 66 includes multiple resistors R1, R2, ..., Rn-1, Rn (where n is a natural number). The push switch 61 includes multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n, and an output contact 61out. In the resistor voltage divider circuit 66, the 15V potential is divided according to the number of resistors R1, R2, ..., Rn-1, Rn, generating multiple potentials within the range of 0 to 15V. These generated potentials are then input to each of the multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n. Specifically, input contact 61in_0 is electrically connected to battery 40 without going through multiple resistors R1, R2, ..., Rn-1, Rn, and 15V is input to input contact 61in_0. Input contact 61in_n is electrically connected to GND (0V), and 0V is input to input contact 61in_n. Each of the input contacts 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1 is input with a potential corresponding to the division ratio of the multiple resistors R1, R2, ..., Rn-1, Rn. That is, each of the multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n is input with a potential of a different magnitude.

[0057] The potential generated by the resistive voltage divider circuit 66 is a stepped (discontinuous) potential within the range of 0 to 15V. The potentials input to the multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n decrease from 15V to 0V in this order, but the interval between the potentials input to two adjacent input contacts may be the same or different.

[0058] When the push button of the push switch 61 is pressed, one of the multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n is selected, and one of the multiple input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n is electrically connected to the output contact 61out. In the push switch 61, each time the push button is pressed, the electrical connection with the output contact 61out may be switched in the order of input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n, or the electrical connection with the output contact 61out may be switched in the order of input contacts 61in_n, 61in_n-1, 61in_n-2, ..., 61in_2, 61in_1, 61in_0. Alternatively, the electrical connection with the output contact 61out may be switched in the following order: input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n, then return to input contact 61in_0, and again switch in the following order: input contacts 61in_0, 61in_1, 61in_2, ..., 61in_n-2, 61in_n-1, 61in_n, or return to input contact 61in_n-1, and switch in the following order: input contacts 61in_n-1, 61in_n-2, ..., 61in_2, 61in_1, 61in_0.

[0059] Thus, the resistive voltage divider circuit 66 and the push switch 61 can generate multiple potentials in steps from the input potential, and select one of the generated potentials to output. Furthermore, the output potential can be controlled by operating the push button on the push switch 61.

[0060] Referring again to Figure 5, the optical element driving circuit section 60 will be described.

[0061] The optical element driving circuit 60 includes a first output terminal 67_1, a second output terminal 67_2, a third output terminal 67_3, a fourth output terminal 67_4, and a fifth output terminal 67_5. The optical element driving circuit 60 generates a signal to drive the optical element 10, and outputs a first signal S1, a second signal S2, a third signal S3, a fourth signal S4, and a fifth signal S5 from the first output terminal 67_1, the second output terminal 67_2, the third output terminal 67_3, the fourth output terminal 67_4, and the fifth output terminal 67_5, respectively.

[0062] The oscillator OSC is electrically connected to the gates of the first transistor Tr1 and the second transistor Tr2. The oscillator OSC generates and outputs a square wave. The frequency of the square wave is, for example, 60 Hz, but is not limited to this. The square wave output from the oscillator OSC is input to the gates of the first transistor Tr1 and the second transistor Tr2. Therefore, each of the first transistor Tr1 and the second transistor Tr2 alternates between the on and off states depending on the frequency of the square wave.

[0063] One of the sources and drains of the first transistor Tr1 is electrically connected to the output contact of the push switch 61 via contact C1. Contact C1 is electrically connected to the first output terminal 67_1 via node N1. The other source and drain of the first transistor Tr1 is electrically connected to GND (0V). Therefore, when the first transistor Tr1 is ON, the potential of node N1 is 0V. On the other hand, when the first transistor Tr1 is OFF, the potential of node N1 becomes a predetermined potential selected by the operation of the push button of the push switch 61. That is, a first signal S1 having a first pulse wave PW1 with an amplitude of the predetermined potential is output from the first output terminal 67_1 which is electrically connected to node N1. The first pulse wave PW1 has a phase that is the inverted phase of the square wave generated by the oscillator OSC.

[0064] One of the sources and drains of the second transistor Tr2 is electrically connected to the battery 40 via contact C2. Contact C2 is electrically connected to the gate of the third transistor Tr3 via node N2. The other of the sources and drains of the second transistor Tr2 is electrically connected to GND (0V). Therefore, when the second transistor Tr2 is ON, the potential of node N2 is 0V. On the other hand, when the second transistor Tr2 is OFF, the potential of node N2 is 15V. In other words, the potential of node N2 alternates between 0V and 15V depending on the frequency of the square wave.

[0065] The gate of the third transistor Tr3 is electrically connected to node N2. Furthermore, one of the source and drain of the third transistor Tr3 is electrically connected to the output contact of the push switch 61 via contact C3. Contact C3 is electrically connected to the second output terminal 67_2 via node N3. Additionally, the other of the source and drain of the third transistor Tr3 is electrically connected to GND (0V). Therefore, when the third transistor Tr3 is ON, the potential of node N3 is 0V. On the other hand, when the third transistor Tr3 is OFF, the potential of node N3 becomes a predetermined potential selected by the operation of the push button on the push switch 61. That is, a second signal S2 having a second pulse wave PW2 with an amplitude of the predetermined potential is output from the second output terminal 67_2, which is electrically connected to node N3. The second pulse wave PW2 has the same phase as the square wave generated by the oscillator OSC.

[0066] The third output terminal 67_3 to the fifth output terminal 67_5 are electrically connected to the output contact 61out of the push switch 61. Therefore, the third signal S3 to the fifth signal S5 output from the third output terminal 67_3 to the fifth output terminal 67_5 are connected to a fixed potential P corresponding to a predetermined potential. fixIt has the following. Although not shown in the figures, a resistive voltage divider circuit may be electrically connected to the fifth output terminal 67_5, and a fifth signal S5 having a fixed potential (for example, an intermediate potential of a predetermined potential) generated by the resistive voltage divider circuit may be output from the fifth output terminal 67_5.

[0067] The first signal S1 to the fourth signal S4 generated by the optical element driving circuit 60 are input to the optical element 10. Now, referring to Figure 7, the signals input to the optical element 10 and the driving of the optical element 10 in the lighting device 1 will be explained.

[0068] Figure 7 is a schematic diagram showing the signals input to the optical element 10 of a lighting device 1 according to one embodiment of the present invention. Figure 7 shows the first liquid crystal cell 100-1 of the optical element 10.

[0069] The first signal S1 to the fourth signal S4 are input to the first terminal 122-1 to the fourth terminal 122-4, respectively. The first terminal 122-1 to the fourth terminal 122-4 are electrically connected to the first transparent electrode 120-1 to the fourth transparent electrode 120-4, respectively. Therefore, the first pulse wave PW1 is applied to the first transparent electrode 120-1, the second pulse wave PW2 is applied to the second transparent electrode 120-2, and the fixed potential P is applied to the third transparent electrode 120-3 and the fourth transparent electrode 120-4. fix It is applied.

[0070] The first pulse wave PW1 and the second pulse wave PW2 have the same amplitude, but their phases are inverted. Therefore, a transverse electric field is generated between the first transparent electrode 120-1 and the second transparent electrode 120-2, changing the orientation of the liquid crystal molecules on the first substrate 110-1 side. The third signal S3 and the fourth signal S4 are at the same fixed potential P fixBecause a lateral electric field is applied, no lateral electric field is generated between the third transparent electrode 120-3 and the fourth transparent electrode 120-4, and the orientation state of the liquid crystal molecules on the second substrate 110-2 side does not change. In this case, the light transmitted through the first liquid crystal cell 100-1 is diffused in the y-axis direction. The diffusion angle in the y-axis direction changes depending on the amplitude of the first pulse wave PW1 and the second pulse wave PW2, but the diffusion angle in the y-axis direction can be easily adjusted by operating the push button of the push switch 61.

[0071] Although a detailed explanation is omitted, signals are appropriately input to the second liquid crystal cell 100-2 to the fourth liquid crystal cell 100-4 so that the transmitted light is diffused in the y-axis direction. Therefore, the light emitted from the illumination device 1 has a linear light distribution shape that is extended in the y-axis direction.

[0072] As described above, the lighting device 1 according to this embodiment can emit light having a linear light distribution shape extended in a uniaxial direction (y-axis direction). The light distribution angle of the light emitted from the lighting device 1 is controlled in steps by operating the push button of the push switch 61. That is, by pressing the push button of the push switch 61, the user can change the output from the output side contact 61out in steps. This makes it possible to change the amplitude of the first pulse wave PW1 and the second pulse wave PW2 in steps. Since the amplitude of each pulse wave corresponds to the potential difference between the transparent electrodes 120 of each liquid crystal cell 100 of the optical element 10, the larger the amplitude of the pulse wave, the larger the potential difference between the transparent electrodes. In this case, the refractive index distribution of the liquid crystal molecules becomes larger, and the light distribution angle of the light becomes larger. Also, the smaller the amplitude of the pulse wave, the smaller the potential difference between the transparent electrodes. In this case, the refractive index distribution of the liquid crystal molecules becomes smaller, and the light distribution angle of the light also becomes smaller. In this way, the light distribution angle of the light emitted from the lighting device 1 can be easily adjusted simply by pressing the push switch 61. Furthermore, when the push switch 61 is pressed, the fixed potential P fix The size can also be changed.

[0073] The lighting device 1 is capable of various modifications. Below, several modifications of the optical element driving circuit section 60 of the lighting device 1 are described. Note that in the following, descriptions of configurations similar to those of the optical element driving circuit section 60 may be omitted.

[0074] <Example 1> Referring to Figure 8, a modified example of the optical element driving circuit 60, the optical element driving circuit 60A, will be described.

[0075] Figure 8 is a block diagram showing the circuit configuration of the optical element driving circuit section 60A of the lighting device 1 according to one embodiment of the present invention.

[0076] The first output terminal 67_1 and the third output terminal 67_3 are electrically connected to node N1. Therefore, each of the first signal S1 output from the first output terminal 67_1 and the third signal S3 output from the third output terminal 67_3 has a first pulse wave PW1. The second output terminal 67_2 and the fourth output terminal 67_4 are electrically connected to node N3. Therefore, each of the second signal S2 output from the second output terminal 67_2 and the fourth signal S4 output from the fourth output terminal 67_4 has a second pulse wave PW2. The fifth output terminal 67_5 is electrically connected to the output contact 61out of the push switch 61. Therefore, the fifth signal S5 output from the fifth output terminal 67_5 has a fixed potential P corresponding to a predetermined potential. fix It has.

[0077] The first signal S1 to the fourth signal S4 are input to the first terminal 122-1 to the fourth terminal 122-4, respectively. The first terminal 122-1 to the fourth terminal 122-4 are electrically connected to the first transparent electrode 120-1 to the fourth transparent electrode 120-4, respectively. Therefore, the first pulse wave PW1 is applied to the first transparent electrode 120-1 and the third transparent electrode 120-3, and the second pulse wave PW2 is applied to the second transparent electrode 120-2 and the fourth transparent electrode 120-4.

[0078] The first pulse wave PW1 and the second pulse wave PW2 have the same amplitude, but their phases are inverted. As a result, a transverse electric field is generated between the first transparent electrode 120-1 and the second transparent electrode 120-2, changing the orientation of the liquid crystal molecules on the first substrate 110-1 side. Also, a transverse electric field is generated between the third transparent electrode 120-3 and the fourth transparent electrode 120-4, changing the orientation of the liquid crystal molecules on the second substrate 110-2 side. In this case, the light transmitted through the first liquid crystal cell 100-1 is diffused in the x-axis and y-axis directions. Therefore, the light irradiated from the illumination device 1 according to this modified example has a circular light distribution shape that is diffused in the x-axis and y-axis directions.

[0079] As described above, the lighting device 1 according to this modified example can emit light having a circular light distribution shape. The light distribution angle of the light emitted from the lighting device 1 is controlled in steps by operating the push button of the push switch 61. In other words, the user can easily adjust the light distribution angle of the light emitted from the lighting device 1 simply by pressing the push button of the push switch 61.

[0080] <Modification 2> Referring to Figure 9, a modified example of the optical element driving circuit 60, the optical element driving circuit 60B, will be described.

[0081] Figure 9 is a block diagram showing the circuit configuration of the optical element driving circuit section 60B of the lighting device 1 according to one embodiment of the present invention.

[0082] The optical element driving circuit 60B includes a first output terminal 67_1, a second output terminal 67_2, a third output terminal 67_3, a fourth output terminal 67_4, a fifth output terminal 67_5, and a sixth output terminal 67_6. The optical element driving circuit 60B generates a signal to drive the optical element 10, and outputs a first signal S1, a second signal S2, a third signal S3, a fourth signal S4, a fifth signal S5, and a sixth signal S6 from the first output terminal 67_1, the second output terminal 67_2, the third output terminal 67_3, the fourth output terminal 67_4, the fifth output terminal 67_5, and the sixth output terminal 67_6, respectively.

[0083] The optical element driving circuit section 60B includes two push switches 61 and two resistive voltage divider circuits 66. In the optical element driving circuit section 60B, the resistive voltage divider circuits 66 and the push switches 61 are used not only for generating the first signal S1 and the second signal S2, but also for generating the third signal S3 and the fourth signal S4. Specifically, a circuit connected to one of the two push switches 61 includes a first output terminal 67_1, a second output terminal 67_2, and a fifth output terminal 67_5, and the first signal S1, the second signal S2, and the fifth signal S5 are output from each of the first output terminal 67_1, the second output terminal 67_2, and the fifth output terminal 67_5, respectively. Furthermore, the circuit connected to the other of the two push switches 61 includes a third output terminal 67_3, a fourth output terminal 67_4, and a sixth output terminal 67_6, from which the third signal S3, the fourth signal S4, and the sixth signal S6 are output, respectively.

[0084] In the optical element driving circuit section 60B, each of the first signal S1 and the third signal S3 has a first pulse wave PW1, each of the second signal S2 and the fourth signal S4 has a second pulse wave PW2, and each of the fifth signal S5 and the sixth signal S6 has a fixed potential P corresponding to a predetermined potential. fix It has.

[0085] The first signal S1 to the fourth signal S4 are input to the first terminal 122-1 to the fourth terminal 122-4, respectively. The first terminal 122-1 to the fourth terminal 122-4 are electrically connected to the first transparent electrode 120-1 to the fourth transparent electrode 120-4, respectively. Therefore, the first pulse wave PW1 is applied to the first transparent electrode 120-1 and the third transparent electrode 120-3, and the second pulse wave PW2 is applied to the second transparent electrode 120-2 and the fourth transparent electrode 120-4.

[0086] The first pulse wave PW1 and the second pulse wave PW2 have the same amplitude, but their phases are inverted. As a result, a transverse electric field is generated between the first transparent electrode 120-1 and the second transparent electrode 120-2, changing the orientation of the liquid crystal molecules on the first substrate 110-1 side. Also, a transverse electric field is generated between the third transparent electrode 120-3 and the fourth transparent electrode 120-4, changing the orientation of the liquid crystal molecules on the second substrate 110-2 side. In this case, the light transmitted through the first liquid crystal cell 100-1 is diffused in the x-axis and y-axis directions. Therefore, the light irradiated from the illumination device 1 according to this modified example has a circular light distribution shape that is diffused in the x-axis and y-axis directions.

[0087] As described above, the lighting device 1 according to this modified example can emit light having a circular light distribution shape. The light distribution angle of the light emitted from the lighting device 1 is controlled in steps by operating the push button of the push switch 61. That is, the user can easily adjust the light distribution angle of the light emitted from the lighting device 1 simply by pressing the push button of the push switch 61. In addition, in the lighting device 1 according to this modified example, the amplitudes of the first pulse wave PW1 and the second pulse wave PW2 of the first signal S1 and the second signal S2, and the amplitudes of the first pulse wave PW1 and the second pulse wave PW2 of the third signal S3 and the fourth signal are controlled by each push switch 61. Therefore, in the lighting device 1 according to this modified example, the light distribution angle in the x-axis direction and the light distribution angle in the y-axis direction can be adjusted separately and independently, and not only a circular shape but also an elliptical light distribution shape can be formed.

[0088] <Second Embodiment> Referring to Figures 10 and 11, a lighting device 2 according to one embodiment of the present invention will be described. Note that in the following description, the explanation of configurations similar to those of lighting device 1 may be omitted.

[0089] Figure 10 is a schematic block diagram showing the internal configuration of a lighting device 2 according to one embodiment of the present invention.

[0090] As shown in Figure 10, the lighting device 2 includes an optical element 10, a light source 20, an optical adjustment unit 30, a battery 40, a charging module 50, an optical element drive circuit unit 60, and a light source drive circuit unit 70. The optical element drive circuit unit 60 of the lighting device 2 is connected not only to a push switch 61 but also to a push switch 62. Specifically, the push switch 62 is positioned between the optical element drive circuit unit 60 and the optical element 10. In other words, the optical element 10 is electrically connected to the optical element drive circuit unit 60 via the push switch 62. The push button of the push switch 62 is provided on the upper surface of the main body 1a, similar to the push button of the push switch 61. For example, the push button of the push switch 62 is positioned on the upper surface of the main body 1a, alongside the push button of the push switch 61 in the z-axis or x-axis direction. However, the position of the push button of the push switch 62 is not limited to this configuration. The push button of the push switch 62 may be provided on the side of the main body 1a.

[0091] The push switch 62 controls the light distribution shape of the light emitted from the lighting unit 1b. In other words, when the user presses the push button on the push switch 62, the light distribution shape of the light emitted from the lighting unit 1b changes. To put it another way, the push switch 62 can switch the light distribution shape by controlling the signal input to the optical element 10. The following describes the signal input to the optical element 10 and the driving of the optical element 10 in the lighting device 2 with reference to Figure 11.

[0092] Figure 11 is a schematic diagram showing the signals input to the optical element 10 of a lighting device 2 according to one embodiment of the present invention. Figure 11 shows the first liquid crystal cell 100-1 of the optical element 10.

[0093] The push switch 62 includes multiple input contacts 62in_1, 62in_2, 62in_3, and 62in_4, and multiple output contacts 62out_1 and 62out_2. In the push switch 62, output contact 62out_1 is electrically connected to one of the input contacts 62in_1 and 62in_2, and output contact 62out_2 is electrically connected to one of the input contacts 62in_3 and 62in_4. The electrical connections of the output contacts 62out_1 and 62out_2 in the push switch 62 are interlocked. When output contact 62out_1 is electrically connected to input contact 62in_1, output contact 62out_2 is electrically connected to input contact 62in_3. On the other hand, when output contact 62out_1 is electrically connected to input contact 62in_2, output contact 62out_2 is electrically connected to input contact 62in_4. Each time the push button on push switch 62 is pressed, the electrical connection of the output contacts 62out_1 and 62out_2 is switched.

[0094] As shown in Figure 11, the first signal S1 and the second signal S2 are input to input contacts 62in_1 and 62in_3, respectively. In addition, the fifth signal is input to input contacts 62in_2 and 62in_4.

[0095] When the output contacts 62out_1 and 62out_2 are electrically connected to the input contacts 62in_1 and 62in_3, respectively, the first signal S1 and the second signal S2 are input to the first terminal 122-1 and the second terminal 122-2, respectively. In addition, the third signal S3 and the fourth signal S4 are input to the third terminal 122-3 and the fourth terminal 122-4, respectively. As a result, the first pulse wave PW1 is applied to the first transparent electrode 120-1 and the third transparent electrode 120-3, and the second pulse wave PW2 is applied to the second transparent electrode 120-2 and the fourth transparent electrode 120-4.

[0096] In this case, a transverse electric field is generated between the first transparent electrode 120-1 and the second transparent electrode 120-2, changing the orientation of the liquid crystal molecules on the first substrate 110-1 side. Also, a transverse electric field is generated between the third transparent electrode 120-3 and the fourth transparent electrode 120-4, changing the orientation of the liquid crystal molecules on the second substrate 110-2 side. Therefore, the light transmitted through the first liquid crystal cell 100-1 is diffused in the x-axis and y-axis directions. Consequently, the light irradiated from the illumination device 2 has a circular light distribution shape that is diffused in the x-axis and y-axis directions.

[0097] When the output contacts 62out_1 and 62out_2 are electrically connected to the input contacts 62in_2 and 62in_4, respectively, the fifth signal S5 is input to the first terminal 122-1 and the second terminal 122-2. Also, the third signal S3 and the fourth signal S4 are input to the third terminal 122-3 and the fourth terminal 122-4, respectively. Therefore, the first transparent electrode 120-1 and the second transparent electrode 120-2 are subjected to a fixed potential P fix A voltage is applied, and the first pulse wave PW1 is applied to the third transparent electrode 120-3, and the second pulse wave PW2 is applied to the fourth transparent electrode 120-4.

[0098] In this case, no transverse electric field is generated between the first transparent electrode 120-1 and the second transparent electrode 120-2, and the orientation of the liquid crystal molecules on the first substrate 110-1 side does not change. On the other hand, a transverse electric field is generated between the third transparent electrode 120-3 and the fourth transparent electrode 120-4, and the orientation of the liquid crystal molecules on the second substrate 110-2 side changes. Therefore, the light transmitted through the first liquid crystal cell 100-1 is diffused in the x-axis direction. Consequently, the light irradiated from the illumination device 2 has a linear light distribution shape extended in the x-axis direction.

[0099] In the above description, for convenience, a configuration in which the push switch 62 is connected to the first liquid crystal cell 100-1 has been explained. However, it is preferable that the push switch 62 is also connected to the second liquid crystal cell 100-2 to the fourth liquid crystal cell 100-4. In this case, each of the four push switches 62 may be connected to the first liquid crystal cell 100-1 to the fourth liquid crystal cell 100-4, and each of the multiple contacts of a single switch may be electrically connected to the first terminal 122-1 to the fourth terminal 122-4 of the first liquid crystal cell 100-1 to the fourth liquid crystal cell, respectively. Although details are omitted, the connection between the terminals of each liquid crystal cell 100 (first terminal 122-1 to fourth terminal 122-4) and the push switch 62 may change depending on the light distribution shape. In the lighting device 2, various light distribution shapes can be formed using the push switches 62.

[0100] As described above, in the lighting device 2 according to this embodiment, the light distribution shape can be switched between circular and linear by operating the push button of the push switch 62, and light can be emitted accordingly. Furthermore, the light distribution angle of the light emitted from the lighting device 2 can be controlled in steps by operating the push button of the push switch 61. In other words, the user can easily adjust the light distribution shape and light distribution angle of the light emitted from the lighting device 2 simply by pressing the respective push buttons of the push switch 62 and the push switch 61.

[0101] Each embodiment, including variations, can be combined with one another, provided that no technical inconsistencies arise.

[0102] Within the scope of the concept of the present invention, those skilled in the art will understand that various modifications and alterations may be considered equivalent to the present invention, and that such modifications and alterations also fall within the scope of the present invention. For example, any addition, deletion, or design change of components, or addition, omission, or modification of processes, made by those skilled in the art to the above-described embodiments, are also included within the scope of the present invention, as long as they retain the gist of the present invention.

[0103] Furthermore, any other effects and advantages brought about by each embodiment that are evident from the description herein or that can be appropriately conceived by those skilled in the art are naturally considered to be brought about by the present invention. [Explanation of Symbols]

[0104] 1, 2: Lighting device, 1a: Main unit, 1b: Lighting unit, 10: Optical element, 20: Light source, 30: Optical adjustment unit, 40: Battery, 50: Charging module, 60, 60A, 60B: Optical element driving circuit unit, 61: Push switch, 61in: Input side contact, 61out: Output side contact, 62: Push switch, 62in: Input side contact, 62out: Output side contact, 66: Resistive voltage divider circuit, 67: Output terminal, 70: Light source driving circuit unit, 71: Light source adjustment switch, 100: Liquid crystal cell, 100-1: First liquid crystal cell, 100-2: Second liquid crystal cell, 100-3: Third liquid crystal cell, 100-4: Fourth liquid crystal cell, 110-1: First substrate, 110-2: Second substrate, 120: Transparent electrode, 120-1: First transparent electrode, 120-2: Second transparent electrode, 120-3: Third transparent electrode, 120-4: Fourth transparent electrode, 121-1: First connection pad, 121-2: Second connection pad, 121-3: Third connection pad, 121-4: Fourth connection pad, 122-1: First terminal, 122-2: Second terminal, 122-3: Third terminal, 122-4: Fourth terminal, 130-1: First alignment film, 130-2: Second alignment film, 140: Sealing material, 150: Liquid crystal layer, 160: Optical elastic resin layer, 1000-1: First light, 1000-2: Second light, C1, C2, C3: Contacts, N1, N2, N3: Nodes, OSC: Oscillator, R1, R2, Rn-1, Rn: Resistors, S1: First signal, S2: Second signal, S3: Third signal, S4: Fourth signal, S5: Fifth signal, S6: Sixth signal, Tr1: First transistor, Tr2: Second transistor, Tr3: Third transistor

Claims

1. Light source and An optical element including a first liquid crystal cell that diffusely transmits light emitted from the light source, An optical element driving circuit unit connected to the optical element and generating a signal for driving the optical element, It includes a push button operated by the user and a first push switch connected to the optical element driving circuit section, The first liquid crystal cell is A first substrate having alternating first transparent electrodes and second transparent electrodes extending in a first direction, A second substrate having alternating third and fourth transparent electrodes extending in a second direction intersecting the first direction, The liquid crystal layer between the first substrate and the second substrate, The optical element driving circuit section is, A first resistive voltage divider circuit is electrically connected to a plurality of input contacts of the first push switch, A first output terminal is electrically connected to the output contact of the first push switch and outputs a first signal having a first pulse wave, The first push switch includes a second output terminal which is electrically connected to the output contact of the first push switch and outputs a second signal having a second pulse wave in which the phase of the first pulse wave is inverted, The first signal is input to the optical element such that the first pulse wave is applied to the first transparent electrode. The second signal is input to the optical element such that the second pulse wave is applied to the second transparent electrode. A lighting device wherein, each time the push button of the first push switch is pressed, one of the plurality of input contacts electrically connected to the output contact is selected, and the amplitudes of the first pulse wave and the second pulse wave change in steps.

2. The optical element driving circuit section further comprises: A third output terminal is electrically connected to the output contact of the first push switch and outputs a third signal having a fixed potential, It includes a fourth output terminal that is electrically connected to the output contact of the first push switch and outputs a fourth signal having the fixed potential, The third signal is input to the optical element such that the fixed potential is applied to the third transparent electrode. The illumination device according to claim 1, wherein the fourth signal is input to the optical element such that the fixed potential is applied to the fourth transparent electrode.

3. The optical element driving circuit section further comprises: A third output terminal is electrically connected to the output contact of the first push switch and outputs a third signal having the first pulse wave, It includes a fourth output terminal that is electrically connected to the output contact of the first push switch and outputs a fourth signal having the second pulse wave, The third signal is input to the optical element such that the first pulse wave is applied to the third transparent electrode. The illumination device according to claim 1, wherein the fourth signal is input to the optical element such that the second pulse wave is applied to the fourth transparent electrode.

4. Furthermore, it includes a push button operated by the user and a second push switch connected to the optical element driving circuit section, The optical element driving circuit section is, A second resistive voltage divider circuit is electrically connected to a plurality of input contacts of the second push switch, A third output terminal is electrically connected to the output contact of the second push switch and outputs a third signal having a third pulse wave, The device includes a fourth output terminal electrically connected to the output contact of the second push switch, to which a fourth signal having a fourth pulse wave obtained by inverting the phase of the third pulse wave is output, The third signal is input to the optical element such that the third pulse wave is applied to the third transparent electrode. The fourth signal is input to the optical element such that the fourth pulse wave is applied to the fourth transparent electrode. The lighting device according to claim 1, wherein each time the push button of the second push switch is pressed, one of the plurality of input contacts electrically connected to the output contact is selected, and the amplitudes of the third pulse wave and the fourth pulse wave change in steps.

5. Light source and An optical element including a first liquid crystal cell that diffusely transmits light emitted from the light source, An optical element driving circuit unit connected to the optical element and generating a signal for driving the optical element, A first push switch, which includes a first push button operated by the user and connected to the optical element driving circuit, A second push switch includes a second push button operated by the user, the first input contact, second input contact, third input contact, and fourth input contact being electrically connected to the optical element drive circuit, and the first output contact and second output contact being electrically connected to the optical element, The first liquid crystal cell is A first substrate having alternating first transparent electrodes and second transparent electrodes extending in a first direction, A second substrate having alternating third and fourth transparent electrodes extending in a second direction intersecting the first direction, The liquid crystal layer between the first substrate and the second substrate, The optical element driving circuit generates a first signal having a first pulse wave, a second signal having the phase of the first pulse wave inverted, and a third signal having a fixed potential. The first signal and the second signal are input to the first input contact and the second input contact of the second push switch, respectively. The third signal is input to the third input contact and the fourth input contact of the second push switch. Each time the second push button of the second push switch is pressed, one of the first input contact and the second input contact, which are electrically connected to the first output contact, is selected, and one of the third input contact and the fourth input contact, which are electrically connected to the second output contact, is selected. A lighting device in which the first pulse wave and the second pulse wave are applied to the first transparent electrode and the second transparent electrode, respectively, or the fixed potential is applied to the first transparent electrode and the second transparent electrode.

6. The lighting device according to claim 5, wherein the optical element driving circuit section changes the amplitude of the first pulse wave and the second pulse wave in steps each time the first push button of the first push switch is pressed.

7. The optical element driving circuit further generates a fourth signal having the first pulse wave and a fifth signal having the second pulse wave. The fourth signal is input to the optical element such that the first pulse wave is applied to the third transparent electrode. The illumination device according to claim 5, wherein the fifth signal is input to the optical element such that the second pulse wave is applied to the fourth transparent electrode.

8. Furthermore, the lighting device according to any one of claims 1 to 7 includes a light source adjustment switch that is operated to adjust the brightness of the light source.

9. The lighting device according to claim 8, wherein the light source adjustment switch is a slide switch capable of continuously adjusting the brightness of the light source.

10. The lighting device according to claim 8, wherein the light source adjustment switch is a push switch capable of adjusting the brightness of the light source in steps.

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