JP2016096060A - Lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lighting device which improves in luminance uniformity of an irradiation surface to which light is projected.SOLUTION: A lighting device includes a light source and an optical system. The optical system projects light from the light source, and also controls distribution of the projected light so that a light distribution curve from a vertical angle of 0° as a light axis to a beam angle of 1/10 turns into a linear fashion.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a lighting device that projects light.

  2. Description of the Related Art Conventionally, lighting devices such as projectors used in stadiums, for example, have a narrow-angle light distribution characteristic because the irradiation surface is far away.

  1/10 beam angle indicating the degree of beam opening as an index indicating the light distribution characteristic (an angle from the vertical angle 0 °, which is the optical axis with the highest luminous intensity, and the luminous intensity is 1/10 of the luminous intensity of the optical axis) ) In the conventional illuminating device, the ratio of the luminous intensity near the vertical angle of 0 ° is high, and the light distribution curve has an inflection point in the range of the vertical angle of 0 ° to 1/10 beam angle.

JP 2014-86159 A

  The conventional lighting device has a high luminous intensity ratio near the vertical angle of 0 ° and a light distribution curve having an inflection point in the range of the vertical angle of 0 ° to 1/10 beam angle. There is a problem that the ratio of the luminous intensity in the vicinity of an angle of 0 ° is high, and the illuminance on the irradiated surface is likely to be uneven.

  The problem to be solved by the present invention is to provide an illuminating device capable of improving the illuminance uniformity of the irradiated surface on which light is projected.

  The illumination device of the embodiment includes a light source and an optical system. The optical system projects light from the light source and controls the light distribution of the emitted light so that the light distribution curve from the vertical angle 0 ° to the 1/10 beam angle, which is the optical axis, is linear. To do.

  According to the present invention, it can be expected to improve the illuminance uniformity of the irradiation surface that projects light from the lighting device.

It is a graph of the light distribution curve of the light which the illuminating device which shows one Embodiment projects. It is a perspective view of an illuminating device same as the above. It is an illuminance distribution figure of the irradiation surface which irradiates light from an illumination device same as the above. It is an illuminance distribution figure of the irradiation surface which irradiates light from the light projector of a comparative example. It is an illuminance distribution map of the irradiation surface in a stadium using a plurality of the same illumination devices. It is an illuminance distribution map of the irradiation surface in a stadium using a plurality of floodlights of comparative examples. It is a graph which shows the relationship between a vertical angle and a spherical zone light beam in an illumination device same as the above. It is a table | surface which shows the ratio of a spherical zone light beam for every 5 degrees of vertical angles with respect to the spherical zone light beam of the range of 0-15 degrees of vertical angles in an illuminating device same as the above.

  Hereinafter, an embodiment will be described with reference to FIGS. 1 to 8.

  FIG. 2 shows the lighting device 10. The illumination device 10 is a projector used in a stadium, for example. The lighting device 10 includes a main body 11, a power supply unit 12, and an installation base 13 for installing the main body 11 and the power supply unit 12.

  The main body 11 has a case 16 whose front surface is open and a translucent cover 17 that closes the front surface of the case 16. A plurality of light sources 18 are disposed inside the main body 11, and reflectors 19 that condense light from the light sources 18 and control light distribution are disposed for each light source 18. The reflector 19 constitutes an optical system 20 that projects the light from the light source 18 and controls the light distribution of the projected light. In addition to the reflector 19, the optical system 20 may use a lens or other optical components.

  The light source 18 uses a light emitting element 21 such as an LED. The light source 18 is mainly a light source 18 that generates white light, but may be combined with a light source 18 that generates red light or blue-green light in order to improve color reproducibility.

  Further, the power supply unit 12 supplies power to each light source 18 and turns on each light source 18.

  Then, a plurality of lighting devices 10 are installed on the upper part of the pillars erected on the stadium, on the roof of the stadium, etc., and irradiate the stadium with light.

  Next, FIG. 1 shows a graph of a light distribution curve of light projected by the illumination device 10.

  The horizontal axis of the graph indicates the vertical angle when the optical axis z (see FIG. 2) of the center of the light projected by the optical system 20 is set to 0 °. The vertical axis of the graph shows the relative ratio of luminous intensity when the highest luminous intensity of light projected by the optical system 20 is 1. 1/10 beam angle indicating the degree of opening of the beam as an index indicating the light distribution characteristic (the angle from the vertical angle 0 ° which is the optical axis z having the highest luminous intensity, and the luminous intensity is 1/10 of the luminous intensity at the optical axis z) This 1/10 beam angle has a relative ratio of luminous intensity of 0.1.

  In the light distribution curves A and B, the 1/10 beam angle is at a vertical angle of 15 °, and the inflection points A1 and B1 are at the vertical angle of the 1/10 beam angle (vertical angle of 15 °). The light distribution curve A is a light distribution curve that approximates a straight line from a vertical angle of 0 ° to a 1/10 beam angle. The light distribution curve B is a light distribution curve in which the relative ratio of the luminous intensity from the vertical angle of 0 ° to the 1/10 beam angle is higher than that of the light distribution curve A.

  Further, the light distribution curve C has a 1/10 beam angle at a vertical angle of 15 ° and an inflection point C1 at a vertical angle of 1/10 beam angle. The light distribution curve C is linear from a vertical angle of 0 ° to a 1/10 beam angle.

  Note that the inflection points A1, B1, and C1 may be at a vertical angle equal to or greater than 1/10 beam angle.

  Moreover, the light distribution curve D shows the light distribution curve which the conventional light projector has as a comparative example. The light distribution curve D has a high luminous intensity ratio in the vertical angle range of 0 to 5 °, and has an inflection point D1 in the range of the vertical angle from 0 ° to 1/10 beam angle. The 1/10 beam angle is about 11 ° in the vertical angle.

  The illuminating device 10 of this embodiment has one of the light distribution curves A, B, or C. These light distribution curves A, B or C are controlled by the setting of the optical system 20.

  The light distribution curves A and B can be expressed numerically by, for example, Gompertz curves. The Gompertz curve is expressed by the following equation.

  The Gompertz curve parameters are K: 1 (fixed), x: x coordinate of the inflection point, b: y coordinate of the inflection point, and c: inclination.

  The light distribution curve A is represented by a Gompertz curve with K = 1, x = 15, b = 0.1, and c = −0.15.

  The light distribution curve B is represented by a Gompertz curve with K = 1, x = 15, b = 0.1, and c = −0.5.

  The light distribution curve C is represented by a Gompertz curve with K = 1, x = 15, b = 0.1, and c = (value smaller than −0.15).

  FIG. 3 shows an illuminance distribution diagram of an irradiation surface on which light is emitted from the illumination device 10 in the case of the light distribution curve A. In FIG. 4, the illumination intensity distribution figure of the irradiation surface which irradiates light from the conventional projector of the light distribution curve D is shown as a comparative example. As shown in FIG. 4, in the case of the light distribution curve D, when the instrument luminous flux is the same, the central luminous intensity is particularly higher than that of the light distribution curve D, so that the illuminance around the irradiation point is extremely high. For this reason, illuminance unevenness occurs from the illuminance difference in the irradiation surface, and the illuminance uniformity (minimum value / average value) decreases. On the other hand, as shown in FIG. 3, in the case of the light distribution curve A, since the central luminous intensity is relatively low, uneven illuminance on the irradiated surface is suppressed, and the illuminance uniformity can be improved.

  Further, the light distribution curve B is the same as the light distribution curve A, and the illuminance uniformity can be improved.

  Therefore, if K = 1, x = 15, b = 0.1 and the range of c is in the range of −0.5 ≦ c ≦ −0.15, the illuminance uniformity can be improved. That is, as shown in FIG. 1, the light intensity distribution curve in the range of the vertical angle 0 ° to 1/10 beam angle is in the range between the light distribution curve A and the light distribution curve B, so that the central luminous intensity is relative. Thus, the illuminance uniformity can be improved by suppressing the uneven illuminance on the irradiated surface.

  In the case of the light distribution curve C, the same tendency as that of the light distribution curve A is obtained, and the illuminance uniformity can be improved. Therefore, the light distribution curve in the range of the vertical angle from 0 ° to 1/10 beam angle is more preferably in the range between the light distribution curve A and the light distribution curve B. Even in the range between B and B, since the central luminous intensity is relatively lower than that of the light distribution curve D, the illuminance uniformity can be improved.

  FIG. 5 shows an illuminance distribution diagram of the ground area, which is an irradiation surface in a stadium using a plurality of lighting devices 10 having a light distribution curve A. FIG. 6 shows an illuminance distribution diagram of an irradiation surface in a stadium using a plurality of conventional projectors having a light distribution curve D as a comparative example. As can be seen from FIGS. 5 and 6, even in a situation where a plurality of illumination devices 10 of the present embodiment are used, the illuminance uniformity of the irradiated surface in the ground area can be improved.

  FIG. 7 is a graph showing the relationship between the vertical angle and the spherical luminous flux in the illumination device 10. The horizontal axis of the graph indicates the vertical angle, and the vertical axis indicates the luminous intensity of the bulb. The spherical zone luminous intensity is obtained by multiplying the average luminous intensity in the horizontal angle direction at the vertical angle θ by the spherical zone coefficient at the vertical angle θ. Note that the sphere coefficient is used when obtaining the total luminous flux of the instrument, and is shown in JIS8105-5: 2011.

  A curve AA is a case of a light distribution curve A represented by a Gompertz curve with K = 1, x = 15, b = 0.1, and c = −0.15. A curve BB is a case of a light distribution curve B represented by a Gompertz curve with K = 1, x = 15, b = 0.1, and c = −0.5. A curve DD is a case of a light distribution curve D of a conventional projector as a comparative example. It should be noted that the lighting device 10 of this embodiment and the conventional projector have the same luminous flux (110,000 lm).

  FIG. 8 is a table showing the ratio of the spherical light flux at a vertical angle of 5 ° to the spherical light flux at a vertical angle of 0 to 15 °. That is, it indicates how much the spherical luminous flux within the vertical angle of 0 to 15 ° is included for each vertical angle.

  In the case of the conventional projector, that is, the light distribution curve D, the spherical luminous flux concentrates in the range of the vertical angle of 0 to 5 °, and the spherical luminous flux in each of the vertical angle of 5 to 10 ° and the vertical angle of 10 to 15 ° is small. It has become.

  On the other hand, in this embodiment, the spherical light flux in the range of the vertical angle of 5 to 10 ° and the vertical angle of 10 to 15 ° is larger than the spherical light flux in the range of the vertical angle of 0 to 5 °.

  When the ratio of the vertical angle of 5 ° to 15 ° in the spherical light flux within the range of the vertical angle of 0 ° to 15 ° becomes larger than the light distribution curve D, the illumination device 10 of the present embodiment has a light distribution with a low central luminous intensity. It becomes a shape and the illuminance uniformity on the irradiated surface can be improved.

  As described above, according to the illumination device 10 of the present embodiment, it is possible to improve the illuminance uniformity of the irradiated surface.

  That is, by controlling the light distribution of the light emitted from the lighting device 10 to a light distribution in which the light distribution curve from a vertical angle of 0 ° to a 1/10 beam angle is linear, the central luminous intensity is relatively low. Furthermore, since the illuminance distribution on the irradiated surface is such that the illuminance decreases at approximately equal intervals without a steep gradient, the illuminance uniformity on the irradiated surface can be improved most. Also. Even in a shape in which the light distribution curve swells more than a linear shape, the central luminous intensity can be relatively lowered, so that the illuminance uniformity on the irradiated surface can be improved.

  There is no inflection point of the light distribution curve from the vertical angle 0 ° to less than 1/10 beam angle, and the light distribution curve of the light emitted from the illuminating device 10 has a vertical angle greater than 1/10 beam angle. By controlling the light distribution having an inflection point, the illuminance uniformity on the irradiated surface can be improved.

  The light distribution of the light projected from the illuminating device 10 is such that the light distribution curve from a vertical angle of 0 ° to a 1/10 beam angle is K = 1, b = 0.1, x = 15 and −0.5 ≦ c. By controlling the light distribution represented by a Gompertz curve that satisfies the range of ≦ −0.15, the illuminance uniformity on the irradiated surface can be improved.

  The distribution of the light projected from the illumination device 10 is such that the ratio of the spherical luminous flux in the vertical angle range of 5-10 ° to the vertical luminous flux in the range of vertical angle of 0-15 ° is 0.45% or more, and the vertical angle is 0. By controlling the light distribution so that the ratio of the spherical light flux in the vertical angle range of 10-15 ° to the spherical light flux in the range of ˜15 ° is 0.29% or more, the illuminance uniformity on the irradiated surface is improved. Can do.

  Furthermore, in the illumination device 10 of the present embodiment, when the total luminous flux is the same as that of the conventional projector, the central luminosity is lower than that of the conventional projector, so that the maximum illuminance of the vertical plane as well as the horizontal irradiation surface is reduced. Since the overall horizontal plane illuminance is substantially the same, not only the illuminance uniformity can be improved, but also the GR value (glare value), which is an evaluation index of the uniformity glare, can be reduced.

  Moreover, in the illuminating device 10 of this embodiment, the luminous intensity more than 1/10 beam angle can be suppressed from the conventional projector, and in addition to illuminating the irradiation surface efficiently, the illuminating device 10 is viewed from an oblique direction. Since the brightness of the light emitting surface at the time can be reduced, the range in which the user feels dazzling when viewing the illumination device 10 directly can be narrowed.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 Lighting equipment
18 Light source
20 Optical system

Claims (3)

With a light source;
An optical system for projecting the light from the light source and controlling the light distribution of the projected light so that the light distribution curve from the vertical angle 0 ° to the 1/10 beam angle as the optical axis is linear. When;
An illumination device comprising: With a light source;
The light from the light source is projected, and the light distribution of the projected light is a light distribution curve having the highest luminous intensity at a vertical angle of 0 °, which is the optical axis, and is distributed at a vertical angle of 1/10 beam angle or more. An optical system for controlling the light distribution having an inflection point of the light curve;
An illumination device comprising: With a light source;
The light of the light source is projected and the light distribution of the projected light is set to a vertical angle of 5 to 10 ° in a spherical luminous flux with a vertical angle of 0 to 15 ° and an optical axis of 0 °. A light distribution in which the ratio of the spherical luminous flux is 0.45% or more and the proportion of the spherical luminous flux in the vertical angle range of 10 to 15 ° is 0.29% or higher in the spherical luminous flux in the range of the vertical angle of 0 to 15 °. An optical system to control;
An illumination device comprising: