Optical unit

Abstract

An optical unit (18) includes: a first light source (20) in which a plurality of light-emitting elements are arranged in an array; a rotary reflector (22) that rotates while reflecting the light emitted from the first light source (20); and a control unit (29) that controls the lighting states of the plurality of light-emitting elements. The rotary reflector (22) is provided with a reflecting surface so that the light scanned while rotating and reflected forms a light distribution pattern as a light source image. The plurality of light-emitting elements include a first light-emitting element and a second light-emitting element. The control unit (29) controls the lighting states of the first light-emitting element and the second light-emitting element such that the lighting time (T1) of the first light-emitting element is longer than the lighting time (T2) of the second light-emitting element (T2 > 0).

Description

Technical Field

[0001] The present invention relates to an optical unit, and more particularly to an optical unit used in a vehicle lamp. Background Art

[0002] In recent years, a device has been designed that reflects light emitted from a light source to the front of a vehicle and scans the area in front of the vehicle with the reflected light to form a prescribed light distribution pattern. For example, an optical unit has been designed that includes a rotating reflector that reflects light emitted from a light source and rotates in one direction about a rotation axis, and a plurality of light sources composed of light emitting elements. The rotating reflector is provided with a reflecting surface such that the light of the light source reflected while rotating forms a desired light distribution pattern (Patent Document 1).

[0003] In addition, the optical unit can form a non-irradiation area in a part of the light distribution pattern by extinguishing the light emitting element at a prescribed timing.

[0004] [Prior Art Documents]

[0005] [Patent Documents]

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2015-26628 Summary of the Invention

[0007] [Problems to be Solved by the Invention]

[0008] However, the above-described optical unit limits the shape of the light distribution pattern that can be formed, and there is room for further improvement.

[0009] The present invention has been made in view of such circumstances, and an object thereof is to provide a new optical unit that can form a plurality of light distribution patterns with a simple structure.

[0010] [Means for Solving the Technical Problems]

[0011] In order to solve the above problems, an optical unit according to an aspect of the present invention includes: a light source in which a plurality of light emitting elements are arranged in an array; a rotating reflector that rotates while reflecting light emitted from the light source; and a control unit that controls the lighting states of the plurality of light emitting elements. The rotating reflector is provided with a reflecting surface such that the light reflected while rotating and scanned forms a light source image to form a light distribution pattern. The plurality of light emitting elements include a first light emitting element and a second light emitting element. The control unit controls the lighting states of the first light emitting element and the second light emitting element such that the lighting time T1 of the first light emitting element is longer than the lighting time T2 of the second light emitting element (T2>0).

[0012] According to this solution, it is possible to make the length of the region formed by the light source image by scanning the light emitted from the first light-emitting element different from the length of the region formed by the light source image by scanning the light emitted from the second light-emitting element. Thus, compared with the case where the state of each light-emitting element can only be selected from either normal lighting or normal turning off, more light distribution patterns with different shapes can be formed.

[0013] Alternatively, in the light source, the first light-emitting element and the second light-emitting element may be arranged in a direction intersecting the direction in which the light source image is scanned. Thus, a stepped light distribution pattern can be formed with a small number of light-emitting elements.

[0014] Alternatively, the plurality of light-emitting elements may further include a third light-emitting element. The third light-emitting element is configured to scan the region where the regions scanned by the first light-emitting element and the second light-emitting element overlap, and the control unit can control the output of the third light-emitting element so that the lighting time T3 of the third light-emitting element satisfies T1 > T3 > T2. Thus, a stepped light distribution pattern with a small difference can be formed.

[0015] Alternatively, the control unit controls the lighting states of the plurality of light-emitting elements so that the cut-off line of light and dark on the own driving lane side of the light distribution pattern inclines outward or becomes higher step by step. Thus, for example, a light distribution pattern having an inclined cut-off line of light and dark suitable for a vehicle headlamp can be formed.

[0016] Alternatively, in the light source, the plurality of light-emitting elements are arranged in a matrix of m rows × n columns (m and n are integers of 2 or more), and the light-emitting elements in the k-th column (k is an integer less than or equal to n) are configured to be offset by a 1 / n pitch with respect to the light-emitting elements in the (k - 1)-th column. Thus, a stepped light distribution pattern with a small difference can be formed.

[0017] In addition, any combination of the above components, and converting the expression of the present invention between methods, devices, systems, etc. as the solution of the present invention is also effective.

[0018] [Advantages of the Invention] <00fffff

[0019] According to the present invention, a plurality of light distribution patterns can be formed with a simple structure. Description of the Drawings

[0020] Figure 1 It is a horizontal cross-sectional view of the vehicle headlamp according to this embodiment.

[0021] Figure 2 It is a front view of the vehicle headlamp according to this embodiment.

[0022] Figure 3 It is a side view schematically showing the structure of the rotary reflector according to this embodiment.

[0023] Figure 4 It is a top view schematically showing the structure of the rotary reflector of the present embodiment.

[0024] Figure 5 It is a schematic view when observing the first light source of the present embodiment from the front.

[0025] Figure 6 (a) of is a schematic view showing the case where the first light-emitting part and the third light-emitting part in the lit state are reflected by the stationary rotary reflector and projected forward as a light source image. Figure 6 (b) of is a view showing the first light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector. Figure 6 (a) of is a view showing the first light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector.

[0026] Figure 7 (a) of is a schematic view showing the case where the second light-emitting part in the lit state is reflected by the stationary rotary reflector and projected forward as a light source image. Figure 7 (b) of is a view showing the second light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector. Figure 7 (a) of is a view showing the second light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector.

[0027] Figure 8 (a) of is a schematic view showing the state where the fourth light-emitting part in the lit state is reflected by the stationary rotary reflector and projected forward as a light source image. Figure 8 (b) of is a view showing the third light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector. Figure 8 (a) of is a view showing the third light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector.

[0028] Figure 9 It is a view showing the light distribution pattern PH' for high beam formed when all the light-emitting elements of the first light source and the second light source are lit and scanned.

[0029] Figure 10 It is a view showing the control device of the vehicle headlamp of the present embodiment.

[0030] Figure 11 (a) of is a schematic view showing the state where the first light-emitting part to the third light-emitting part in the lit state are reflected by the stationary rotary reflector and projected forward as a light source image. Figure 11 (b) of is a view showing the fourth light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector. Figure 11 (a) of is a view showing the fourth light distribution pattern formed by scanning the light source image shown in (a) of through the rotation of the rotary reflector.

[0031] Figure 12 (a) of is a schematic view when observing the light source of the second embodiment from the front. Figure 12 (b) of is a view showing the light distribution pattern for high beam formed by the optical unit of the second embodiment. Figure 12Figure (c) shows a light distribution pattern for high beam formed by the optical unit of the second embodiment.

[0032] Figure 13 is a horizontal cross-sectional view of a vehicle headlamp according to the third embodiment.

[0033] Figure 14 is a schematic diagram comparing the sizes of light source images when the outputs of light-emitting elements having rectangular light-emitting surfaces are different.

[0034] Figure 15 is a schematic diagram showing an example of a light distribution pattern.

[0035] Figure 16 Figure (a) shows a schematic diagram of a case where the illuminated light-emitting part of the fourth embodiment is reflected by a stationary rotary reflector and projected forward as a light source image. Figure 16 Figure (b) shows scanning by rotation of the rotary reflector Figure 16 Figure of the fifth light distribution pattern formed by the light source image shown in Figure (a). Detailed Embodiments

[0036] Hereinafter, the present invention will be described based on embodiments with reference to the accompanying drawings. The same or equivalent components, parts, and processes shown in each figure are denoted by the same reference numerals, and repeated descriptions will be appropriately omitted. In addition, the embodiments are merely illustrative and not restrictive of the invention, and all features or combinations thereof described in the embodiments are not necessarily essential features or combinations of the invention.

[0037] The optical unit of the present embodiment can be used in various vehicle lamps. Hereinafter, a case where the optical unit of the present embodiment is applied to a vehicle headlamp in a vehicle lamp will be described.

[0038] [First Embodiment]

[0039] (Vehicle Headlamp)

[0040] Figure 1 is a horizontal cross-sectional view of the vehicle headlamp of the present embodiment. Figure 2 is a front view of the vehicle headlamp of the present embodiment. In addition, in Figure 2 part of the components are omitted.

[0041] The vehicle headlamp 10 of the present embodiment is a right headlamp mounted on the right front end of an automobile, and has the same structure as the headlamp mounted on the left except for being symmetrical left and right. Therefore, hereinafter, the right vehicle headlamp 10 will be described in detail, and the description of the left vehicle headlamp will be omitted.

[0042] As Figure 1As shown, the vehicle headlamp 10 includes a lamp body 12 having a recess opening forward. In the lamp body 12, its front opening is covered by a transparent front cover 14 to form a lamp chamber 16. The lamp chamber 16 serves as a space for accommodating an optical unit 18. The optical unit 18 is a lamp unit configured to be able to irradiate both variable high beam and low beam. The variable high beam refers to a light beam controlled in such a way that the shape of the high beam distribution pattern changes. For example, a non-irradiation area (light-shielding part) can be generated in a part of the distribution pattern.

[0043] The optical unit 18 of the present embodiment includes: a first light source 20; a condenser lens 23 as a one-dimensional optical system (optical component) that changes the optical path of the first light L1 emitted from the first light source 20 to face the blade 22a of the rotary reflector 22; a rotary reflector 22 that rotates about the rotation axis R while reflecting the first light L1; a projection lens 24; a second light source 26 disposed between the first light source 20 and the projection lens 24; a diffusing lens 28 as a one-dimensional optical system (optical component) that makes the second light L2 emitted from the second light source 26 face the blade 22a; and a control unit 29.

[0044] Sixteen elements are arranged in a matrix in the first light source 20. Four elements are arranged in a row in the second light source 26.

[0045] The projection lens 24 includes: a condensing part 24a that condenses and projects the first light L1 reflected by the rotary reflector 22 in the light irradiation direction of the optical unit ( Figure 1 left direction); and a diffusing part 24b that diffuses and projects the second light L2 reflected by the rotary reflector 22 in the light irradiation direction of the optical unit. Thereby, the source image can be clearly projected in front of the optical unit 18.

[0046] Figure 3 is a side view schematically showing the structure of the rotary reflector of the present embodiment. Figure 4 is a top view schematically showing the structure of the rotary reflector of the present embodiment.

[0047] The rotary reflector 22 is rotated in one direction about the rotation axis R by a drive source such as a motor 34. In addition, the rotary reflector 22 is provided with blades 22a as reflecting surfaces to form a desired distribution pattern by scanning and reflecting the light of each light source while rotating. That is, through this rotation operation, the rotary reflector emits visible light from the light emitting part as an irradiation light beam, and forms a desired distribution pattern by scanning the irradiation light beam.

[0048] The rotary reflector 22 is provided with two blades 22a having the same shape around the cylindrical rotary portion 22b, which function as reflecting surfaces. The rotation axis R of the rotary reflector 22 is inclined with respect to the optical axis Ax and is disposed in a plane including the optical axis Ax and each light source. In other words, the rotation axis R is disposed substantially parallel to the scanning plane of the light (irradiation light beam) of each light source scanned in the left-right direction by rotation. Thereby, thinning of the optical unit is achieved. Here, the scanning plane can be understood as, for example, a fan-shaped plane formed by continuously connecting the trajectories of the lights of the respective light sources serving as scanning lights.

[0049] In addition, the shape of the blade 22a of the rotary reflector 22 has a shape that twists in such a way that the angle formed by the optical axis Ax and the reflecting surface changes as it approaches the circumferential direction centered on the rotation axis R. Thereby, as Figure 4 shown, it is possible to perform scanning using the light of the first light source 20 or the second light source 26.

[0050] Each light source uses a semiconductor light-emitting element such as an LED, an EL element, or an LD element. The shape of the convex projection lens 24 having the condensing portion 24a and the diffusing portion 24b can be appropriately selected according to the required light distribution characteristics such as the light distribution pattern or the illuminance distribution, and an aspherical lens or a free-form surface lens can be used.

[0051] The control unit 29 performs on / off control of the first light source 20 and the second light source 26 and rotation control of the motor 34 according to an external control signal. The first light source 20 is mounted on the heat sink 30, and the second light source 26 is mounted on the heat sink 32.

[0052] Figure 5 is a schematic view when observing the first light source of the present embodiment from the front. In addition, in Figure 5 , the illustration of the condensing lens 23 is omitted. In addition, Figure 5 the light source image of is flipped up and down by the projection lens 24.

[0053] As Figure 5 shown, the first light source 20 has: a first light-emitting portion 36 that is lit when forming a first light distribution pattern in a range mainly irradiating below the horizontal line; a second light-emitting portion 38 that is lit when forming a second light distribution pattern in a range irradiating at least above the horizontal line; and a third light-emitting portion 40 that emits light constituting the cut-off line of light and dark on the side of the own driving lane near the horizontal line when forming the first light distribution pattern. The third light-emitting portion 40 is disposed in a region between the first light-emitting portion 36 and the second light-emitting portion 38.

[0054] The five first light-emitting elements S11 to S15 of the first light-emitting unit 36 are arranged in a zigzag pattern along the horizontal direction (H-H line) (in other words, the vertical position of a certain element is offset upward or downward relative to an adjacent element). The first light-emitting elements S11 to S15 each have a rectangular light-emitting surface, and one side of the rectangle is arranged along the horizontal direction.

[0055] In the second light-emitting unit 38, nine second light-emitting elements S21 to S29 are arranged in a zigzag pattern along the horizontal direction. The second light-emitting elements S21 to S29 each have a rectangular light-emitting surface, and one side of the rectangle is arranged along the horizontal direction.

[0056] The third light-emitting unit 40 has two third light-emitting elements S31 to S32 arranged between the first light-emitting elements S11 to S15 and the second light-emitting elements S21 to S29, and one side of the rectangular light-emitting surface of the third light-emitting element is arranged along the horizontal direction. Thus, it is not easy to generate a dark portion in the light distribution pattern due to the gap between the elements.

[0057] In addition, each light-emitting element is preferably a semiconductor light-emitting element that is easy to perform on / off control in a short time, such as an LED (Light Emitting Device: light-emitting diode), an LD (Laser Diode: laser diode), or an EL (Electroluminescent: electroluminescent) element.

[0058] Figure 6 Figure (a) shows a schematic diagram of the case where the first light-emitting unit and the third light-emitting unit in the lit state are reflected by a stationary rotary reflector and projected forward as a light source image. Figure 6 Figure (b) shows the scanning Figure 6 of the first light distribution pattern formed by the light source image shown in Figure (a).

[0059] Figure 6 The light source images L11 to L15 shown in Figure (a) correspond to the respective light-emitting surfaces of the first light-emitting elements S11 to S15. In addition, the light source images L31 to L32 correspond to the respective light-emitting surfaces of the third light-emitting elements S31 to S32. In addition, by scanning the light source images L11 to L15, L31 to L32, Figure 6 the scanning patterns P11 to P15, P31 to P32 shown in Figure (b) are formed, and by overlapping each scanning pattern, a low-beam light distribution pattern PL as the first light distribution pattern that mainly irradiates the range below the horizontal line is formed.

[0060] In addition, if the third light-emitting elements S31 to S32 are continuously lit in the same manner as the first light-emitting elements S11 to S15, then as Figure 6As shown in (b), in the low beam light distribution pattern PL, not only the cut-off line CL1 on the own lane side is formed above the horizontal line, but also the cut-off line CL2 on the oncoming lane side is formed above the horizontal line. At this time, glare may be generated for the passengers of oncoming vehicles.

[0061] Therefore, the control unit 29 controls the lighting state of the first light source 20 so that the lighting time of the third light emitting elements S31 to S32 when forming the low beam light distribution pattern PL is shorter than the lighting time of the first light emitting elements S11 to S15. More specifically, at the timing when the light source images L31 to L32 of the third light emitting elements S31 to S32 pass through the left region of the V-V line shown in (b) Figure 6 the control unit 29 turns on the corresponding elements, and at the timing when the light source images L31 to L32 of the third light emitting elements S31 to S32 pass through the right region of the V-V line, the control unit 29 turns off the corresponding elements. Thereby, for example, only the upper end of the cut-off line CL1 on the own lane side can be raised. In addition, by controlling the lighting and extinguishing of the third light emitting elements S31 to S32 while scanning the light emitted from the third light emitting elements S31 to S32, the position (length) of the cut-off line CL1 on the own lane side can be changed.

[0062] Figure 7 (a) is a schematic view showing a case where the second light emitting part in the lighting state is reflected by the stationary rotary reflector and projected forward as a light source image, Figure 7 (b) is a view showing the second light distribution pattern formed by scanning the light source image shown in (a) Figure 7 by the rotation of the rotary reflector.

[0063] Figure 7 The light source images L21 to L29 shown in (a) correspond to the respective light emitting surfaces of the second light emitting elements S21 to S29. In addition, by scanning the light source images L21 to L29, Figure 7 the scanning patterns P21 to P29 shown in (b) are formed, and by overlapping the respective scanning patterns, a high beam light distribution pattern PH as a second light distribution pattern that irradiates at least the range above the horizontal line is formed. In addition, the first light emitting part 36 can be turned on when forming the high beam light distribution pattern PH. Thereby, a new light distribution pattern in which the low beam light distribution pattern PL and the high beam light distribution pattern PH are overlapped can be realized.

[0064] Next, the second light source 26 will also be described. Compared to the position where the first light L1 emitted from the first light source 20 is reflected by the blade of the rotary reflector 22, the second light L2 emitted from the second light source 26 is reflected by the blade of the rotary reflector 22 at a position closer to the projection lens 24. Therefore, in order to irradiate a wider range, it is preferable to diffuse the light emitted from the second light source 26. Accordingly, a diffusion lens 28 is disposed near the light emitting surface of the second light source 26. Thereby, the light source image generated by the second light L2 reflected by the rotary reflector 22 and passing through the diffusion portion 24b of the projection lens 24 can be increased. In addition, the second light source 26 has a fourth light emitting portion 42 in which four fourth light emitting elements S41 to S44 are arranged in a row (see Figure 1 ).

[0065] Figure 8 FIG. (a) of Figure 8 is a schematic view showing a case where the fourth light emitting portion in the lit state is reflected by a stationary rotary reflector and projected forward as a light source image, Figure 8 FIG. (b) of Figure 8 is a view showing the third light distribution pattern formed by scanning the light source image shown in Figure 8 (a) of .

[0066] Figure 8 The light source images L41 to L44 shown in (a) of Figure 8 correspond to the respective light emitting surfaces of the fourth light emitting elements S41 to S44. In addition, by scanning the light source images L41 to L44, the scanning patterns P41 to P44 shown in Figure 8 (b) of are formed, and by overlapping the respective scanning patterns, a diffusion low beam light distribution pattern PL' as a third light distribution pattern that mainly irradiates a wide range below the horizontal line is formed.

[0067] Figure 9 FIG. Figure 9 is a view showing a high beam light distribution pattern PH' formed when all the light emitting elements of the first light source and the second light source are lit and scanned. As Figure 9 shown, new light distribution patterns other than the first light distribution pattern and the second light distribution pattern can be realized.

[0068] As described above, the optical unit 18 of the present embodiment can use a rotary reflector 22 that rotates in one direction about a rotation axis while reflecting the light emitted from the first light source 20 or the second light source 26 to form a plurality of light distribution patterns (PL, PL', PH, PH') with different irradiation ranges.

[0069] In addition, the first light emitting portion 36 and the second light emitting portion 38 may be provided as completely different regions as in the first light source 20 of the present embodiment, but a part of the light emitting elements or light emitting regions may be repeated. That is, in any of the cases of the first light distribution pattern and the second light distribution pattern, the light emitting elements or light emitting regions may be used.

[0070] Figure 10 This is a diagram showing the control device for a vehicle headlamp according to the present embodiment. As Figure 10 shown, the control device 100 for the vehicle headlamp 10 according to the present embodiment includes: a camera 44 that captures the front or the surroundings of the vehicle; a radar 46 that detects the presence or the distance to other vehicles or pedestrians in front of the vehicle; a switch 48 that controls the lighting state or the irradiation mode (selection of a high-beam light distribution pattern or a low-beam light distribution pattern or an automatic control mode, etc.) of the vehicle headlamp through a driver; a detection unit 50 that detects the steering operation state (steering state); a sensor 52 such as a vehicle speed sensor or an acceleration sensor; a control unit 29; a motor 34; a first light source 20; and a second light source 26.

[0071] The control unit 29 controls the rotation of the motor 34 and controls the lighting and extinguishing of each light-emitting element in the first light-emitting part 36 to the fourth light-emitting part 42 included in the first light source 20 or the second light source 26 based on the information acquired from the camera 44, the radar 46, the switch 48, the detection unit 50, and the sensor 52. Thereby, a new optical unit 18 capable of forming a plurality of light distribution patterns with a simple structure can be realized.

[0072] In addition, in the case of the low-beam light distribution pattern PL obtained by overlapping the scanning patterns P11 to P15, P31 to P32 as shown in (b) of Figure 6 , or Figure 7 in the case of the high-beam light distribution pattern PH obtained by overlapping the scanning patterns P21 to P29 as shown in (b) of

[0073] , the lengths of the respective scanning patterns are substantially the same. That is, the lighting times of the respective light-emitting elements corresponding to the respective scanning patterns are approximately the same. Therefore, the shapes of the light distribution patterns that can be formed by controlling the lighting or extinguishing of the light-emitting elements are limited.

[0073] Therefore, the control unit 29 is configured to be able to control the lighting times of the plurality of light-emitting elements included in each light source individually or in groups. Thereby, it is possible to combine scanning patterns with different lengths to form a desired light distribution pattern, and thus an optical unit capable of forming light distribution patterns in many shapes can be realized.

[0074] Figure 11 (a) of Figure 11 is a schematic diagram showing a case where the lit first light-emitting part to the third light-emitting part is reflected by a stationary rotary reflector and projected forward as a light source image, Figure 11 and (b) of

[0075] Figure 11The light source images L11 to L15 shown in (a) correspond to the respective light emitting surfaces of the first light emitting elements S11 to S15. In addition, the light source images L21 to L23, L26, L27 correspond to the respective light emitting surfaces of the second light emitting elements S21 to S23, S26, S27. In addition, the light source images L31 to L32 correspond to the respective light emitting surfaces of the third light emitting elements S31 to S32. In addition, when forming the fourth light distribution pattern PH", the second light emitting elements S24, S25, S28, S29 remain in the extinguished state throughout the period. That is, the lighting time of the second light emitting elements S24, S25, S28, S29 is the shortest.

[0076] On the other hand, the lighting time T1 of one cycle of the first light emitting elements S11 to S15 is the longest, forming Figure 11 the scanning patterns P11 to P15 shown in (b), and by overlapping the respective scanning patterns, the range R1 below the horizontal line is mainly irradiated.

[0077] The lighting time of one cycle of the light emitting element S31 is T31 (T31 < T1), and the lighting time of one cycle of the light emitting element S32 is T32 (T32 < T31 < T1). As shown in Figure 11 (b), the range R2 including the H-H line on the own lane side is mainly irradiated. The range R2 partially overlaps with the range R1.

[0078] The lighting time of one cycle of the light emitting element S21 is T21 (T21 < T1), and the lighting time of one cycle of the light emitting element S23 is T23 (T23 < T21 < T1). As shown in Figure 11 (b), the range R3 directly above the H-H line on the own lane side is mainly irradiated. The range R3 partially overlaps with the range R2.

[0079] The lighting time of one cycle of the light emitting element S22 is T22 (T22 < T1). As shown in Figure 11 (b), the range R4 that overlaps with the upper part of the range R3 is irradiated.

[0080] The lighting time of one cycle of the light emitting element S27 is T27 (T27 < T1). As shown in Figure 11 (b), the range R5 that overlaps with the upper part of the range R4 is irradiated.

[0081] The lighting time of one cycle of the light emitting element S26 is T26 (T26 < T1). As shown in Figure 11 (b), the range R6 that overlaps with the upper part of the range R5 is irradiated.

[0082] In addition, the relationship of the lighting time of each light emitting element is T27 ≤ T32 < T26 < T23 < T22 < T31 < T21 < T1.

[0083] The control unit 29 not only controls the selection of the light-emitting elements to be lit or extinguished, but also forms a fourth light distribution pattern in which the light distribution pattern of the present driving lane side cut-off line that can form a light distribution pattern is inclined outward or stepped up by respectively controlling the lighting time of a plurality of lit light-emitting elements, as shown in (b) of Figure 11 . In this way, the optical unit of the present embodiment can form a light distribution pattern having an inclined cut-off line suitable for a vehicle headlamp.

[0084] As described above, the present embodiment includes an optical unit 18, a first light source 20 in which a plurality of light-emitting elements (S11 to S15, S21 to S29, S31 to S32) are arranged in an array, a rotary reflector 22 that rotates while reflecting the light emitted from the first light source 20, and a control unit 29 that controls the lighting states of the plurality of light-emitting elements. The rotary reflector 22 is provided with a reflecting surface so that the light scanned while rotating is used as a light source image (L11 to L15, L21 to L29, L31 to L32) to form a light distribution pattern. The plurality of light-emitting elements include first light-emitting elements (S11 to S15) and second light-emitting elements (S21 to S29, S31 to S32). The control unit 29 controls the lighting states of the first light-emitting elements and the second light-emitting elements (or third light-emitting elements) so that the lighting time T1 of the first light-emitting elements (S11 to S15) is longer than the lighting time T2 (T2 > 0) of the second light-emitting elements (S21 to S29). In addition, the plurality of light-emitting elements having different lighting times can be any combination.

[0085] The optical unit 18 of the present embodiment can make the length of the region formed by scanning the light emitted from the first light-emitting elements (S11 to S15) as a light source image different from the length of the region formed by scanning the light emitted from the second light-emitting elements (S21 to S29) as a light source image. Thus, compared with the case where each light-emitting element can only be selected from either being normally lit or normally extinguished, more light distribution patterns with different shapes can be formed.

[0086] The first light source 20 arranges the first light-emitting element (S12), the second light-emitting elements (S22, S26), and the third light-emitting element (S31) in a direction intersecting the direction D1 in which the light source image is scanned. Thereby, a stepped light distribution pattern can be formed with a small number of light-emitting elements.

[0087] The third light-emitting element S32 of the present embodiment is configured to scan the overlapping area (area R2) of the area (range R1) scanned by the first light-emitting elements S11 to S15 and the areas (R3 to R6) scanned by the second light-emitting elements S21 to S29. The control unit 29 controls the output of the third light-emitting element S32 such that the lighting time T3 (T32) of the third light-emitting element satisfies T1 > T3 > T2. Thereby, a stepped light distribution pattern with less gradation can be formed.

[0088] In addition, in the first light source 20 of the present embodiment, a plurality of light-emitting elements are arranged in a matrix of m rows × n columns (m and n are integers of 2 or more, m = 5, n = 4 in the first light source 20), and the light-emitting elements in the k-th column (k is an integer less than or equal to n) are arranged with an offset of approximately 1 / 2 pitch with respect to the light-emitting elements in the (k - 1)-th column. At this time, compared with the case where the light-emitting elements in adjacent columns are not offset by 1 / 2 pitch, a stepped light distribution pattern with less gradation can be formed.

[0089] [Second Embodiment]

[0090] The optical unit of the second embodiment is mainly characterized by the different structure of the first light source, and there is no substantial difference from the first embodiment other than this. Therefore, in the following, the first light source will be described in detail.

[0091] Figure 12 (a) of is a schematic view when observing the light source of the second embodiment from the front, Figure 12 (b) of is a diagram showing the high-beam light distribution pattern formed by the optical unit of the second embodiment, Figure 12 (c) of is a diagram showing another high-beam light distribution pattern formed by the optical unit of the second embodiment.

[0092] In Figure 12 In the first light source 120 shown in (a) of, nine light-emitting elements S11' to S31' are arranged in a matrix of m rows × n columns (m and n are integers of 2 or more, m = 3, n = 3 in the first light source 120), and the light-emitting elements S21' to S23' in the k-th column (k is an integer less than or equal to n) are arranged with an offset of 1 / 3 pitch (1 pitch = P') with respect to the light-emitting elements S11' to S13' in the (k - 1)-th column.

[0093] The optical unit 18 using the first light source 120 configured in this way can not only form Figure 12 the high-beam light distribution pattern PH shown in (b) of, but also form Figure 12 the partial high-beam light distribution pattern PH" with an inclined light and dark cut-off line shown in (c) of.

[0094] Figure 12The high beam light distribution pattern PH shown in (b) is obtained by overlapping the scanning patterns P11’ to P33’ formed by scanning the light source images of the light emitting elements S11’ to S33’.

[0095] In addition, Figure 12 The partial high beam light distribution pattern PH” shown in (c) is also obtained by overlapping the scanning patterns P11’ to P33’ formed by scanning the light source images of the light emitting elements S11’ to S3’, but the lighting time of each light emitting element is different.

[0096] The light emitting elements S11’, S21’, and S31’ have the longest lighting time T1’ in one cycle, forming Figure 12 the scanning patterns P11’, P21’, and P31’ shown in (c). By overlapping each scanning pattern, the range R1’ below the horizontal line is mainly irradiated.

[0097] The lighting time of the light emitting element S12’ in one cycle is T12’ (T12’ < T1’), the lighting time of the light emitting element S22’ in one cycle is T22’ (T22’ < T1’), and the lighting time of the light emitting element S32’ in one cycle is T32’ (T32’ < T1’). As Figure 12 shown in (c), the range R2’ including the H-H line on the own lane side and directly above it is mainly irradiated. The range R2’ partially overlaps with the range R1’.

[0098] The lighting time of the light emitting element S13’ in one cycle is T13’ (T13’ < T1’), the lighting time of the light emitting element S23’ in one cycle is T23’ (T23’ < T1’), and the lighting time of the light emitting element S33’ in one cycle is T33’ (T33’ < T1’). As Figure 12 shown in (c), the range R3’ above the H-H line on the own lane side is mainly irradiated. The range R3’ partially overlaps with the range R2’.

[0099] In addition, the relationship of the lighting time of each light emitting element is T13’, T23’, T33’ < T12’, and T22’, T32’ < T1.

[0100] The control unit 29 not only selects the lighting and extinguishing of the light emitting elements, but also controls the lighting time of the multiple lit light emitting elements respectively. As Figure 12 shown in (c), it is possible to form a light distribution pattern in which the cut-off line of light and dark on the own lane side of the light distribution pattern slopes outward or rises stepwise. In this way, the optical unit of the present embodiment can form a light distribution pattern having an inclined cut-off line of light and dark suitable for a vehicle headlamp.

[0101] In addition, the first light source 120 of the second embodiment is arranged with an offset of 1 / 3 pitch from the light-emitting elements in adjacent columns. Therefore, compared with the case where the first light source 20 of the first embodiment is arranged with an offset of approximately 1 / 2 pitch, the difference between the scanning patterns related to the formation of the inclined light and dark cutoff line is smaller. As a result, a light distribution pattern with a smoother inclined light and dark cutoff line is obtained.

[0102] [Third Embodiment]

[0103] In the vehicle headlamp 10 of the first embodiment, the shape of the blade 22a of the rotary reflector 22 has a shape in which the twist changes the angle formed by the optical axis Ax and the reflecting surface as it goes in the circumferential direction centered on the rotation axis R. On the other hand, in the vehicle headlamp 10 of the third embodiment, a polyhedral mirror is used as the rotary reflector, and there is no substantial difference from the first embodiment except for this. Therefore, in the following description, the rotary reflector will be described in detail, and the same reference numerals will be given to the same configurations as those in the first embodiment, and the description will be appropriately omitted.

[0104] Figure 13 is a horizontal cross-sectional view of the vehicle headlamp according to the third embodiment. The vehicle headlamp 110 according to the third embodiment includes a lamp body 12 having a recess opening forward. In the lamp body 12, the front opening thereof is covered with a transparent front cover 14 to form a lamp chamber 16. The lamp chamber 16 serves as a space for accommodating an optical unit 118. The optical unit 118 is a lamp unit configured to be able to irradiate both variable high beam and low beam.

[0105] The optical unit 118 of the present embodiment includes: a light source 220; a condenser lens 23 as a one-dimensional optical system (optical component) that changes the optical path of the first light L1 emitted from the light source 220 and directs it toward the reflecting surface 122a of the polyhedral mirror 122; a polyhedral mirror 122 that rotates around the rotation axis R while reflecting the first light L1; a projection lens 124; and a control unit 29.

[0106] In the light source 220, a plurality of elements are arranged in a matrix. The projection lens 124 condenses and projects the first light L1 reflected by the polyhedral mirror 122 in the light irradiation direction of the optical unit ( Figure 1 left direction). Thereby, the light source image can be clearly projected in front of the optical unit 118.

[0107] The polygonal mirror 122 rotates in one direction about the rotation axis R by a drive source such as a motor. In addition, the polygonal mirror 122 is provided with a reflecting surface 122a so as to form a desired light distribution pattern by scanning and reflecting the light of each light source while rotating. That is, the polygonal mirror 122 emits the visible light from the light emitting unit as an irradiation beam through this rotation operation, and forms a desired light distribution pattern by scanning the irradiation beam.

[0108] The rotation axis R of the polygonal mirror 122 is set to be substantially perpendicular to the optical axis Ax and intersects the plane including the optical axis Ax and the light source 220. In other words, the rotation axis R is set to be substantially orthogonal to the scanning plane of the light (irradiation beam) of the light source scanned in the left - right direction by rotation. In the vehicle headlamp 110 using such a polygonal mirror 122, the above - mentioned various light distribution patterns can also be formed.

[0109] [Fourth Embodiment]

[0110] In the above - mentioned respective embodiments, the light source images projected forward by being reflected by the stationary rotating reflector are all described as rectangles of the same size. However, for each light emitting element having a rectangular light emitting surface, the size of the light source image in the stationary state can be changed by controlling (changing) the magnitude of the input current (power).

[0111] Figure 14 It is a schematic diagram comparing the sizes of light source images when the outputs of light emitting elements having rectangular light emitting surfaces are different. Figure 14 The shown light source image L21 is, for example, the case where the light emitting element emits light at its upper - limit output (light quantity 100%), and the range R21 enclosed by the solid line represents the area with a brightness higher than the specified brightness. In addition, in the case of a general light emitting element such as an LED, there is a tendency that the center of the light emitting surface is the brightest and it becomes darker as it approaches the outer edge of the light emitting surface. In addition, the specified brightness means, for example, the brightness at which the user of the optical unit can recognize the outline of the light distribution pattern when scanning the light source image to form the light distribution pattern.

[0112] Figure The shown light source image L21' is, for example, the case where the light emitting element emits light at half of its upper - limit output (light quantity 50%), and the range 51' enclosed by the solid line represents the area with a brightness higher than the specified brightness. In addition, the range R21' of the light source image L21' is smaller than the range R21 of the light source image L21.

[0113] ​ The shown light source image L21'' is, for example, the case where the light emitting element emits light at 10% of its upper - limit output (light quantity 10%), and the range 51'' enclosed by the solid line represents the area with a brightness higher than the specified brightness. In addition, the range R21'' of the light source image L21'' is smaller than the range R21' of the light source image L21'.

[0114] Thus, by changing the output of the light-emitting element, the range irradiated with a prescribed luminance (the size of the light source image) changes. Therefore, when the rotary reflector 22 rotates while scanning the reflected light as a light source image, by changing the output of the light-emitting element by the control unit 29, a light distribution pattern of a new shape can be formed.

[0115] ​ is a schematic diagram showing an example of the light distribution pattern. As ​ shown, the control unit 29 drives the light-emitting element using the upper limit output and scans the light source image L21 from the left side to the right side of the figure. Then, the control unit 29 starts to decrease the output of the light-emitting element at a prescribed timing, and the size of the light source image gradually decreases from the light source image L21 to the light source images L21' and L21". Thereby, the light distribution pattern P21" is formed. The light distribution pattern P21" is rectangular from the left end region to the central region, and the upper edge E1 and the lower edge E2 of the right end region are inclined. Therefore, the inclined upper edge E1 of the light distribution pattern P21" can be used as an inclined cut-off line of brightness.

[0116] ​ (a) of is a schematic diagram showing a case where the lit light-emitting part of the fourth embodiment is reflected by a stationary rotary reflector and projected forward as a light source image, ​ (b) of is a diagram showing the fifth light distribution pattern formed by scanning the light source image shown in ​ (a) of.

[0117] ​ The light source images L11, L21, L22, and L31 shown in (a) of correspond to the respective light-emitting surfaces of the light-emitting elements S11, S21, S22, and S31. Further, when forming the fifth light distribution pattern PH"', the lighting time T1 of one cycle of the light-emitting element S11 is the longest, and the scanning pattern P11" shown in ​ (b) of is formed. In addition, the light-emitting elements S21, S22, and S31 are controlled such that the output gradually decreases in the latter half of the lighting time of one cycle, and the light distribution pattern P21" shown in ​ or a similar light distribution pattern P22" or P31" is formed. Further, each scanning pattern is formed to partially overlap with an adjacent scanning pattern.

[0118] The control unit 29 not only selects the light-emitting elements to be lit and extinguished, but also controls the lighting time or output of a plurality of lit light-emitting elements respectively, as ​As shown in (b) of the figure, there is a fifth light distribution pattern PH”' in which the cut-off line between light and dark on the side of the driving lane that can form a light distribution pattern inclines outward or rises stepwise. In addition, by controlling so as to gradually increase the output in the first half of the lighting time of one cycle, it is also possible to form a light distribution pattern PH”' in which the cut-off line between light and dark on the oncoming driving lane side of the light distribution pattern inclines outward or rises stepwise. Thus, the optical unit of the present embodiment can form a light distribution pattern having an inclined cut-off line between light and dark suitable for a vehicle headlamp.

[0119] As described above, the present invention has been described with reference to the above-described embodiments, but the present invention is not limited to the above-described embodiments, and combinations or replacements of the components of the embodiments are also included in the present invention. In addition, based on the knowledge of those skilled in the art, combinations or processing sequences of the embodiments can be appropriately adapted, or various design changes can be made to each embodiment, and the embodiments after such modifications should also be included in the scope of the present invention.

[0120] [Description of Reference Numerals]

[0121] 10 Vehicle headlamp; 18 Optical unit; 20 First light source; 22 Rotating reflector; 24 Projection lens; 26 Second light source; 29 Control unit; 34 Electric motor; 36 First light emitting part; 38 Second light emitting part; 40 Third light emitting part; 42 Fourth light emitting part; 100 Control device; 110 Vehicle headlamp; 118 Optical unit; 120 First light source; 122 Polyhedral mirror; 124 Projection lens; 220 Light source.

[0122] [Industrial Applicability]

[0123] The present invention can be used in vehicle lamps.

Claims

1. An optical unit, characterized in that, Comprising: A light source, in which a plurality of light-emitting elements are arranged in an array, A rotating reflector that rotates while reflecting the light emitted from the light source, and A control unit that controls the lighting states of the plurality of light-emitting elements; The rotating reflector is provided with a reflecting surface so that the light scanned while rotating and reflected forms a light distribution pattern as a light source image, The plurality of light-emitting elements include a first light-emitting element, a second light-emitting element, and a third light-emitting element, The third light-emitting element is configured to scan an area that is repeated between the area scanned by the first light-emitting element and the area scanned by the second light-emitting element, The control unit controls the lighting states of the first light-emitting element, the second light-emitting element, and the third light-emitting element so as to satisfy T1 > T3 > T2, and gradually changes the outputs of the second light-emitting element and the third light-emitting element so that the cut-off line of light and dark on the own-lane side of the light distribution pattern inclines outward and becomes higher, where the lighting time of the first light-emitting element is T1, the lighting time of the second light-emitting element is T2, T2 > 0, and the lighting time of the third light-emitting element is T3.

2. The optical unit according to claim 1, wherein: In the light source, the first light-emitting element, the second light-emitting element, and the third light-emitting element are arranged in a direction intersecting the direction in which the light source image is scanned.

3. The optical unit according to any one of claims 1 or 2, wherein: In the light source, the plurality of light-emitting elements are arranged in an m-row × n-column matrix, and the light-emitting elements in the k-th column are configured to be offset by a 1 / n pitch with respect to the light-emitting elements in the (k - 1)-th column, where m and n are integers of 2 or more, and k is an integer not exceeding n.

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