JP2017016737A - Sunlight collection module and light collection panel using the same - Google Patents

Abstract

A solar light collecting module that does not require a tracking mechanism and a solar light collecting panel using the same.
A solar light collecting module has a transparent plate-shaped light collecting plate. The light collector 1 has an inclined surface 1d that reflects sunlight incident from the front surface 1a in the direction of the light condensing region 1e on one side surface 1f on the back surface 1b. A plurality of inclined surfaces 1d are arranged in parallel in the direction of the condensing region 1f, and are provided in a curved shape centered on the condensing region 1e by changing the inclination angle αn between the adjacent inclined surfaces 1d.
[Selection] Figure 4

Description

  The present invention relates to a flat plate-shaped solar light collecting module capable of collecting sunlight without tracking and a light collecting panel using the same.

  Various systems have been proposed in which sunlight is introduced indoors and used for lighting or the like. For example, the sunlight condensing lighting apparatus shown in FIG. 7 is proposed (refer patent document 1). This sunlight condensing illuminating device is a control that controls a condensing unit body in which a plurality of lenses 101 and a sun sensor 102 that detects the position of the sun are integrated with signals from the mechanism unit 103 and the sun sensor 102. The mechanism unit 103 is operated by the unit 104 so as to follow the direction of the sun. One end of the optical fiber 105 is disposed near the focal point of each lens 101, and the collected sunlight is guided into the optical fiber 105. And it irradiates sunlight indoors from the lighting terminal device 106 connected to the other end of the optical fiber 105.

  Further, a device that does not require sun tracking as shown in FIG. 8 has been proposed (see, for example, Patent Document 2). This solar concentrator allows light having a wide angle from the upper surface to radiate to the lower surface side, and a light guide 112 disposed on the lower surface side of the optical functional sheet 111. And a reflecting surface provided on the lower surface 112a of the light guide 112 and one end side surface 112b of the light guide 112 on which incident light is collected.

  This solar concentrator induces sunlight on a wide surface of the one end side surface 112b, and a solar cell or a conversion device 113 such as a heat collecting means is disposed on the entire surface of the one end side surface 112b to power solar energy. Or convert it into heat.

JP-A-6-300925 JP 2007-218540 A

  However, in the case of the solar light collecting and illuminating device described in Patent Document 1, there is a problem in that the light collecting unit main body must always accurately follow the direction of the sun. In addition, these devices must be installed in the transparent dome 107 from the viewpoint of waterproofing and wind pressure resistance, and the light collecting unit main body must be installed at a distance from the roof of the building or the roof for installation in the external environment. I must. Since such a follow-up mechanism and a waterproof wind-pressure structure must be equipped, the cost becomes high. Furthermore, since such a structure is required, the weight increases, and the number of installations provided on the roof is naturally limited. Appearance problems also arise.

  The solar concentrator described in Patent Document 2 has a problem that it is necessary to use the optical functional sheet 111 in order to collect sunlight incident at a wide angle. Moreover, sunlight cannot be guided to other places. For example, when used for lighting, it is necessary to convert sunlight into electric power or the like once by a solar cell, and then guide the electricity to a lighting device such as indoors to light it.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a solar light collecting module capable of collecting sunlight and guiding it to an optical fiber with a simple structure that does not have a tracking mechanism. It is something to be offered.

  A solar light collecting module according to an embodiment of the present invention is a transparent plate-shaped light collecting plate, and reflects sunlight incident from the front surface toward the light collecting region on one side surface of the light collecting plate. A plurality of inclined surfaces are arranged side by side in the direction of the light condensing region, are provided by changing the inclination angle between the adjacent inclined surfaces, and are provided in a curved surface centering on the light condensing region. It has the light-condensing plate which is characterized by the above-mentioned.

  In the solar light collecting module, the inclined surface may be a curved surface convex toward the outside of the light collecting plate in a cross section orthogonal to the inclined surface and parallel to the thickness direction of the light collecting plate.

  In the solar light collecting module, the curvature of the curved surface in a section perpendicular to the inclined surface of the inclined surface and parallel to the thickness direction of the light collecting plate may be equal to the curvature of the curved surface centered on the light collecting region. Good.

  In the solar light collecting module, the height of the inclined surface may be lowered toward the light collecting region.

  A solar light collecting panel according to an embodiment of the present invention is characterized in that a plurality of the solar light collecting modules are juxtaposed on a gantry.

  According to the solar light collecting module according to one embodiment of the present invention, the back surface has a plurality of inclined surfaces that reflect sunlight incident from the front surface in the direction of the light collecting region on one side surface in the direction of the light collecting region. In addition to being provided with different inclination angles between adjacent inclined surfaces, and having a condensing plate provided in a curved shape centering on the condensing region, it is incident from the surface Sunlight is reflected by the inclined surface provided on the back surface and condensed on the condensing region. Since the inclined surface is provided by changing the inclination angle, even if the position of the sun is changed, the inclined surface is appropriately reflected by the inclined surface and is condensed on the condensing region. Therefore, it can be set as a non-tracking type sunlight condensing module.

  In the solar light collecting module, when the inclined surface is a curved surface convex toward the outside of the light collecting plate in a cross section orthogonal to the inclined surface and parallel to the thickness direction of the light collecting plate, the light is reflected by the inclined surface. The collected sunlight can be easily collected in the condensing region.

  In the solar light collecting module, if the curvature of the curved surface in the cross section perpendicular to the inclined surface of the inclined surface and parallel to the thickness direction of the light collecting plate is equal to the curvature of the curved surface centered on the light collecting region, the inclined surface The reflected sunlight can be easily collected in the condensing region.

  In the solar light collecting module described above, when the height of the inclined surface is reduced toward the light collecting region, the reflected light from the inclined surface portion is less likely to collide with the adjacent inclined surface portion, and the light exiting end It is possible to make it easy to reflect and propagate efficiently.

  According to the solar light collecting panel according to one embodiment of the present invention, since a plurality of the solar light collecting modules are juxtaposed on the gantry, the sunlight collected by the respective solar light collecting modules is taken out. Can be used.

It is a perspective view which shows the external appearance image of the sunlight condensing module using the light-condensing plate which concerns on one Embodiment of this invention. It is a perspective view which shows the external appearance image of the sunlight condensing panel which concerns on one Embodiment of this invention. It is a top view of the light-condensing plate used for the sunlight condensing module which concerns on one Embodiment of this invention. It is sectional drawing in the BB cross section of the light-condensing plate shown in FIG. It is the principal part expanded sectional view which expanded and showed the A section of the light-condensing plate shown in FIG. It is a cross-sectional image figure in CC cross section of the light-condensing plate shown in FIG. It is a schematic diagram which shows the example of the conventional sunlight condensing lighting apparatus. It is a schematic diagram which shows the example of the conventional sunlight collector.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing an example of an embodiment of a solar light collecting module 10 of the present invention. FIG. 2 is a perspective view showing an example of an embodiment of the solar light collecting panel 11 when a plurality of solar light collecting modules 10 are arranged in two rows on the gantry 5.

  The solar light collecting module 10 includes a light collecting plate 1. An optical fiber 3 is connected to one side surface 1 f of the light collector 1 via a connector 2. Sunlight enters from the upper surface of the light collector 1, is repeatedly reflected inside the light collector 1, and is condensed on the light condensing region 1 e of the light collector 1. The sunlight is made incident on the optical fiber 3 from the one side surface 1f that is the emission end of the light collection region 1e. Then, the light is propagated through the optical fiber 3 so that sunlight is emitted from the output end of the optical fiber 3. For example, when the optical fiber 3 is guided indoors and a radiating device or the like is attached to the exit end of the optical fiber 3, sunlight can be irradiated into the room and used as illumination light.

  The solar light collecting panel 11 includes one or more solar light collecting modules 10 mounted on, for example, the gantry 5. The sunlight condensing panel 11 is installed in a place with good sunlight, for example, an inclined roof of a general household, a rooftop of a building, a factory building, a vacant land, or the like. In FIG. 2, W is east, E is west, S is south, and N is north. Moreover, each condensing module 10 may install the module of one side among 5 units in the opposite direction.

  Since the sunlight condensing panel 11 has a flat shape, even if it is installed on the roof of a house or the like, it is not conspicuous from the bottom and is unlikely to obstruct the appearance of the building. In addition, since the load due to wind pressure is small, such as during strong winds, restrictions on the number of units installed on the roof can be reduced.

  FIG. 3 is a plan view of the light collector 1. In FIG. 3, for the sake of convenience, the left-right direction is the X-axis direction, and the up-down direction is the Y-axis direction. 4 is a cross-sectional view showing a BB cross section of the light collector 1 of FIG. FIG. 5 is a detailed cross-sectional view of the main part showing the part A of FIG. In addition, since the figure becomes complicated, hatching was omitted. 4 and 5, for the sake of convenience, the left-right direction is the X-axis direction, and the up-down direction is the Z-axis direction. The sunlight collecting module 10 is installed at a predetermined angle so that the X axis of the light collector 1 is parallel to the ecliptic plane and the Z axis is in an optimum direction with respect to the solar altitude.

  Sunlight enters the light collector 1 through the surface 1a from above. In order to suppress the reflection of sunlight at the incident surface and to efficiently enter the light collector 1, the surface 1 a of the light collector 1 is subjected to an antireflection coating by a dielectric multilayer film, or cancellation due to interference of light phases. It is recommended to install an anti-reflection sheet that is used. This improves the incident efficiency of sunlight.

The back surface 1b of the light collector 1 is provided with a plurality of curved inclined surfaces 1d that reflect sunlight in the direction of one side surface 1f. The inclined surface 1d is formed as a curved surface inclined in the X-axis direction in the XZ plane. Therefore, the sunlight incident on the light collector 1 is reflected by the inclined surface 1d,
The light is reflected again by the surface 1a, and finally converged on a condensing region 1e in the vicinity of one side surface 1f (hereinafter also referred to as an emission end 1f). The end face shape of the emitting end 1f is set by the size and number of optical fibers to be connected. For example, when two optical fibers having a diameter of dmm are connected, a rectangular or oval emitting end 1f shape of (d × 2d) mm is obtained.

  Further, the light collector 1 has a fan shape whose width becomes narrower toward the light condensing region 1e in plan view. For this reason, sunlight incident from the front surface 1a is also reflected by the curved inclined surface 1d configured on the back surface 1b side and the side surfaces 1c, and is directed toward the light collection region 1e through reflection in the total reflection region D2. And condensed. Thereafter, the sunlight enters the optical fiber 3 from the exit end 1 b of the light collector 1.

Further, the front surface 1a is inclined to the emission end 1f side at an inclination angle β with respect to the back surface 1b. The back surface is a surface connecting the lower ends of the inclined surface 1d. The light guide space in the light collector 1 is formed so that the thickness decreases toward the emission end 1f side in order to efficiently propagate the reflected light from the inclined surface 1d to the emission end 1f side. That is, the inclination angle of the front surface 1a is an angle β with respect to the back surface 1b surface.
The angle of inclination connecting the upper ends of the respective inclined surfaces 1d formed on the back surface 1b is γ, the incident light guide space in the reflection region D1 is increased, and the light collection region D2 is reflected by the upper surface reflection about once. To reach.

The light collector 1 is made of a light-transmitting material having a refractive index nr, and the side surface 1g opposite to the output end 1f is a spherical reflecting surface, and the reflected light is set to be collected near the output end 1f. . Further, the back surface 1b including the inclined surface 1d formed on the back surface 1b side of the light collector 1, the both side surfaces 1c, and the surface 1a of the total reflection region D2 on the emission end 1f side of the surface 1a also form a high-reflection layer. It is said. The highly reflective layer region is formed in a mirror shape by thin film deposition such as aluminum or silver alloy. The high reflection layer region may be one in which total reflection is easily caused in the light collector 1 by, for example, a dielectric multilayer film.

  As shown in FIG. 3, the planar shape of the light collector 1 is a sector shape having a one-side opening angle ε with respect to the central axis (dashed line). The reference point is the intersection of the side surfaces of each one-side opening angle ε. The condensing region 1e is a region centered on this reference point.

The one-side opening angle ε is set according to the characteristics of the optical fiber 3 to be connected. When the NA of the optical fiber used is 0.5 and the refractive index of the light collector 1 is nr,
ε = sin ⁻¹ (0.5) / nr = 20 °
It becomes. Actually, it is better to make it about 5 degrees larger than that to allow a margin in the incident range. Sunlight enters the surface 1a of the light collector 1 as parallel light at a certain incident angle. This must be narrowed down to a light beam incident on the optical fiber 3 by the inclined surface 1 d of the lower surface 1 b of the light collector 1. Therefore, the inclined surface 1d on the lower surface of the light collector 1 is a convex curved surface outside the light collector 1 in a cross section orthogonal to the inclined surface and parallel to the thickness direction of the light collector, that is, in the XZ plane. Let the radius of curvature of this curved surface be Rn (n = 1 to 1). Similarly, the inclined surface 1d is a curved surface centered on the condensing region 1f in plan view. The radius of curvature of the curved surface in the XY plane is defined as Rn (
n = 1-).

When parallel light is incident on a spherical mirror having a certain radius of curvature Rn, if the incident opening angle ε is as small as about 20 °, the position where the reflected light is collected is approximately Rn / 2. Therefore, if the value of the curvature radius Rn of the curved surface of the inclined surface 1d is set to about twice the optical path length between the inclined surface 1d and the condensing end 1f, sunlight reflected on the inclined surface 1d is collected. The light can be condensed on the light region 1f. The curvature radius Rn (n = 1 to 1) of each inclined surface 1d in the XZ plane is similarly configured to be a curved surface, and is approximately twice the optical path length between the inclined surface 1d and the condensing region 1f. It is set to. The curvature Rn decreases as the radius of curvature R1 furthest from the light condensing region 1f approaches the light condensing region 1f from R2, R3, R4,.

  FIG. 5 is an enlarged view of a portion A shown in FIG. As shown therein, the inclination angle αn (n = 1 to 1) of the inclined surface 1d becomes larger as it approaches the light condensing region 1f. Although the inclined surface 1d is a curved surface, the inclination angle αn is formed by a plane connecting both ends of the inclined surface 1d and a surface connecting the lower vertices of the inclined surface 1d (back surface 1b) as shown in FIG. It is also an angle.

Sunlight enters from the upper surface 1a of the light collector 1 at an incident angle Θi, travels through the light collector 1 at a refraction angle Θr, and enters the inclined surface 1d at an incident angle (Θr + α2−β). Here, β is the inclination angle of the surface 1a of the light collector 1. Further, the case where the light is reflected from the reflecting surface 1g opposite to the emission end face 1f by the inclined surface 1d having the second inclination angle α2 will be described as an example. The refraction angle Θr is
Θr = sin ⁻¹ (sinΘi / nr)
Indicated by

Here, the inclined surface 1d has a spherical shape with a curvature radius Rn. Incident light reflected from the central portion is incident on the surface 1a of the light collector 1 at an incident angle (Θr + 2 (α2−β)). In order for the reflected light of the inclined surface 1d in the light collector 1 to be totally reflected by the surface 1a, the incident angle needs to be larger than the critical angle Θc. The critical angle Θc is
Θc = sin ^-1 (1 / nr)
nr: indicated by the refractive index of the light collector 1 That is, if (Θr + 2 (α2−β))> Θc, the sunlight reflected by the inclined surface 1d is totally reflected inside the surface 1a of the light collector 1. Then, it progresses toward the total reflection region D2 on the exit end 1f side of the light collector 1. The incident light on the inclined surface 1d having other inclination angles α1, α3, etc. is similarly reflected and travels.

  The incident angle Θic of the surface 1a of the light collector 1 at that time is determined by the following equation from the above critical angle condition.

Θic> sin ⁻¹ (nr · sin (Θc−2 (αn−β))
That is, it depends on the inclination angle αn of the inclined surface 1d. The larger the inclination angle αn, the smaller the incident angle Θic for total reflection inside the surface 1a.

Therefore, by combining the inclined surfaces 1d having different inclination angles αn, the range of the incident angle Θic of the light collector 1 as a whole can be increased from the different incident angle ranges of the inclined surfaces 1d. The inclination angle αn is set to gradually increase toward the emission end 1f. Thus, the region where αn is large is in the range of a small incident angle Θi, and the region where αn is small is incident and reflected from a large incident angle Θi.

  FIG. 4 shows an example of ray tracing in which sunlight incident on the sunlight collecting module reaches the light collecting region 1e. In FIG. 4, the case where sunlight injects into the 3rd inclined surface 1d from the opposite side surface 1g side is shown. D1 is a region where the inclined surface 1d is disposed on the back surface 1b, and sunlight enters from the front surface 1a. D2 is an area where the back surface 1b does not have the inclined surface 1d, and instead is totally reflected inside the back surface 1b, both side surfaces 1c and the surface 1a where the reflective layer is formed. In addition, reflective layers are formed on the side surface 1c and the back surface 1b of the D1 region other than the surface 1a portion of the region D1 where sunlight enters.

In FIG. 4, the case where the sunlight which injected from the upper surface of the light-condensing plate 1 injects into the 3rd inclined surface 1d from the left is illustrated. The sunlight reflected by the inclined surface 1d is incident on the surface 1a from the inside of the light collector 1 at an incident angle Θr + 2 (α3−β), and is totally reflected there, and then enters a region D2 where a reflection layer is formed on the entire circumference. Incident. Thereafter, total reflection is repeated several times on the front surface 1a and the back surface 1b to focus on the light condensing region 1e. Then, the light enters the optical fiber 3 connected in close contact with the output end 1f,
It propagates in the optical fiber 3 core.

  Here, the distance from the incident position of the inclined surface 1d to the total reflection surface region D2 is DS2, and the distance from the opposite side 1g side end of the inclined surface 1d to the opposite side surface 1g side boundary of the total reflection surface region D2 is S2. Then, in the case of DS2> S2, it is possible to reach the total reflection surface region D2 by reflecting once on the surface 1a of the light collector 1, and after several internal reflections, the optical fiber via the output end 1f. 3 is incident on the incident end. In the case of DS2 <S2, the light enters the other inclined surface 1d, and the incident sunlight is scattered. The total reflection region is a portion obtained by subtracting D1 from the total length D of the light collector 1, and this is the total reflection region D2.

  Table 1 shows the result of calculating the incident angle range of each inclined surface 1d configured on the lower surface 1b of the light collector 1. αn represents an inclination angle of each inclined surface 1d. Θimin indicates the minimum value of the incident angle Θi on the upper surface of the light collector 1. Θimax indicates the maximum value of the incident angle Θi on the upper surface of the light collector 1. DSn indicates a distance that can be reached by reflection once from each inclined surface 1d at the minimum incident angle. Sn indicates the distance between each inclined surface 1d and the end of the total reflection region D2. These values are calculated assuming that the refractive index nr of the light collector 1 is 1.5 and the inclination angle β of the surface 1a is 6 °.

From Table 1, when the inclination angle αn = 30 °, the reflected sunlight from the inclined surface 1d is reflected once on the inner surface 1a of the light collector 1 in the range where Θi is approximately 35 ° or more and 60 ° or less. Thus, since DSn> Sn, the total reflection region D2 is reached. When the tilt angle αn = 31 °, the incident angle is 2
The light reaches the total reflection region D2 only by being reflected once on the inner surface of the surface 1a within a range of 0 ° to 55 °. The larger the inclination angle α of the inclined surface 1d, the more the light can reach the total reflection region D2 even at a small incident angle Θi on the surface 1a of the light collector 1.

  For example, when the incident direction of sunlight is from the back surface 1g side, the solar incident light reflected by the region where the inclined surface 1d of the inclined surface 1d on the back surface 1g side is small enters the total reflection region D2, and gradually enters the sunlight. As the direction moves and the incident direction becomes the exit end 1f side, the light reflected by the region with the large tilt angle of the inclined surface 1d on the exit end 1f side enters the total reflection region D2. Since the reflection operation is performed at different inclined surface angles of the inclined surface 1d depending on the incident angle, the light condensing function toward the total reflection region D2 is performed over a wide incident angle range of the sunlight incident angle Θi.

  That is, in the morning, when the solar altitude reaches a certain height (incident angle Θi is 60 ° or less), the sunlight reflected by the first inclined surface 1d farthest from the emission end 1f reaches the condensing region 1e. become. Thereafter, as the sun climbs, the sunlight reflected by the adjacent second inclined surface 1d also reaches the condensing region 1e. When the sun approaches the south-central altitude (incidence angle Θi is around ± 20 °), the sunlight reflected by the first and second inclined surfaces 1d, etc. does not reach the condensing region 1e, but instead, the exit end 1f Sunlight reflected by the plurality of inclined surfaces 1d on the side closer to the light reaches the light collection region 1e.

On the other hand, the height hn of each inclined surface 1d is gradually lowered toward the emission end 1f side. Accordingly, vignetting due to the inclined surface 1d on the emission end 1f side can be made difficult to occur, and the influence that the reflected light is blocked by the inclined surface 1d on the emission end 1f side and cannot reach the condensing region 1f can be reduced. The height hn of the inclined surface 1d means the length between the upper end and the lower end of the inclined surface 1d in the direction parallel to the Z axis.

The height hn (n = 1 to 1) of each inclined surface 1d becomes lower so as to come into contact with two planes that intersect at an angle γ as it goes toward the emission end 1f. The angle γ is indicated by tan ⁻¹ (h1 / D1). Here, h1 is the height of the inclined surface 1d farthest from the emission end 1f, D1 is the length of the region where the inclined surface 1d of the back surface 1b is installed, and even the length of the region D1 where sunlight is incident. is there.

As a result, the length of each inclined surface 1d on the X-axis is also different from l1, l2, l3..., And becomes shorter as it approaches the emission end 1f.

  Thereafter, the outgoing light from the outgoing end 1 f is directly incident on the end of the optical fiber 3 connected to the end face having the same refractive index as that of the light collector 1 and propagates. The connector 2 is a support that holds the connection between the light collector 1 and the optical fiber 3. The connection between the output end 1f and the end of the optical fiber 3 may be a simple butting or a spatial connection whose end face is processed into a lens shape. The connector 2 is a support for connecting and fixing the output end 1 f of the light collector 1 having such a structure and the ends of the optical fiber 3. In addition, although connection with the light-condensing plate 1 was set as the connection by the optical fiber 3 this time, in addition to this, a fiber pandle in which many small-diameter fibers are bundled, or a flexible light guide having a larger outer diameter may be used. The optical fiber 3 of the present invention refers to all such light guiding structures, and can be used properly depending on the application.

  Next, FIG. 6 is a cross-sectional view showing a C-C cross section of the light collector 1 shown in FIG. 3. The hatching is omitted. As shown in FIG. 6, the light collector 1 has a cylindrical surface having a gentle curvature R <b> 1 on the back surface 1 b side and a curvature R <b> 2 on the front surface 1 a side. Thereby, when incident light repeatedly guides total reflection toward the output end 1f, it can be condensed in the Z-axis direction. R1 and R2 are set to have a large curvature so that incident sunlight is condensed at a length equal to or longer than the total length D of the light collector 1. By setting the surface 1a to have a curvature R1 and the back surface 1b to have a curvature R2, even when incident sunlight is incident at an incident angle Θa with respect to the upper surface 1a of the light collector 1 and the Z axis, the upper surface lens action and the lower surface spherical mirror It is condensed in the Z-axis direction by the action.

Both side surfaces 1c have inclined surfaces with an angle Θb with respect to the Y axis. For example, if the installation is based on the equinox and autumn equinox, the variation of the south-central altitude at the summer solstice and winter solstice times with respect to the equinox and equinox is ± Θa,
Θb = sin ⁻¹ (sinΘa / nr)
Set by Note that nr is the refractive index of the light collector 1.

As a result, when the south-middle altitude of the Equinox and Autumn Equinox days is taken as the Z-axis reference, much of the incident light from the surface 1a of the light-condensing plate 1 can be obtained even if the south-central altitude of the sun fluctuates by ± Θa. And can be reflected on the inclined surface 1d and propagated in the X-axis direction. In addition, by making the surface 1a of the light collector 1 into a curved surface having a curvature R2, the area of sunlight incident on the light collector 1 can be increased as compared with the case where it is flat, and the lens effect causes the emission end 1f. On the other hand, since the light can be condensed on the central axis Z, it contributes to the improvement of the incident efficiency of sunlight (the intensity of the emitted light from the emission end 1f / the intensity of the incident light from the incident surface 1a).

  Similarly, by making the lower surface of the light collector 1 a curved surface having a curvature R1, it acts as a spherical mirror in the section C-C. Can be mitigated by the light condensing effect of the spherical mirror having the curvature R1.

  A plurality of such sunlight condensing modules 10 are installed on the mount 5 or the like and used as the solar panel 11. The sunlight collecting module 10 is installed so that the X-axis direction coincides with the east-west direction, and the Y-axis direction coincides with north-south.

Furthermore, if the X axis of each solar light collecting module 10 is the central axis, the maximum ± Θa is obtained depending on the season.
A mechanism for rotating the total 2Θa is added. As a result, the sunlight always stays in the X-axis (
It can be incident at an incident angle from the vertical Z-axis direction (east-west), and the incident-angle fluctuation is mitigated by the seasonal fluctuation of the south-south altitude on the Y-axis side depending on the season, and each sunlight is condensed more efficiently and stably. The light can enter the module 4.

The range of the incident angle Θi of sunlight can be set to −75 ° to + 60 ° from Table 1, for example. That is, the incident angle range can be about 135 °. In addition, in the case of an inclined roof installation, the same thing can be installed on the opposite side to allow almost all-day incidence from sunrise to sunset. Further, if 2 to 4 solar light collecting modules 10 are used for one illumination, the illumination optical fiber 3 is taken from the light collecting modules 4 on both of the installation roofs, and can be stably solarized from morning to afternoon. Incident light can be captured.

  Further, by using the solar light collecting module 10 in combination with another general lighting device, it is possible to reduce the power of the lighting device. For example, when it is used together with an LED illuminator with an illuminance sensor and it is cloudy when the weather worsens, it can be used for smart illumination that interpolates the illumination by switching the illumination to the LED illuminator. In addition, although the flexible light guide like the optical fiber 3 was connected with respect to the light-condensing plate 1 so far, the application example for illumination was shown, However, this invention may be used for the other use, A light-condensing plate A plurality of concentrating solar cell elements can be installed at one output end 1f, and can be utilized as a flat-plate-concentrating concentrating solar cell in which electric power is extracted by photoelectric conversion. In addition, a heat collecting pipe wall can be installed at the exit end 1f, where it can be used as a heat collector for collecting heat, exchanging heat with the fluid inside the pipe wall, and heating the fluid in the pipe.

  Next, a specific example of the solar light collecting module 10 of the present invention will be described.

As the material of the light collector 1, an optical plastic such as a polymethyl methacrylate resin having a refractive index of 1.49 to 1.6 can be used. It is cut into a predetermined shape by machining or molding. The material of the light collector 1 may be other translucent resin material or optical glass material. In the above embodiment, a translucent plastic resin material of polymethyl methacrylate resin having a refractive index nr = 1.5 is used after being machined.

The light collector 1 has the shape shown in FIG. 3 and has a length D = 415 mm, a width W 350 mm, and an opposite side surface 1 g.
Has a height of 67 mm, the inclination angle β of the surface 1a with respect to the X axis is 6 °, and the exit end 1b has a height 4 × width 8
It is a rectangular shape of mm. It has a substantially fan-like shape in top view and front view.

  On the back surface 1 b of the light collector 1, an inclined surface 1 d having an inclination angle α of 30 to 41 ° is formed. Table 2 shows design parameters of these inclined surfaces 1d.

The inclined surface 1d has curved surfaces with curvatures such that the optical path distance Rn is an equal distance in the XY plane and the XZ plane with the condensing region 1e as the center. Further, the inclination angle γ connecting the vertices of the inclined surfaces 1d was set to 6 degrees. The sunlight incident region D1 is 265 mm, the total reflection region D2 is 150 mm, the both side surfaces 1c of the light collector 1, the back surface 1b including the inclined surface 1d, and the front surface 1a of the total reflection region D2 are silver-tin, silver-indium, silver -A reflective layer of nickel alloy or the like was applied by vacuum deposition. Further, two plastic fibers having a core diameter of 2.9 mm, a cladding diameter of 3 mm, an NA (fiber numerical aperture: incident angle) of 0.5, and a length of 10 m are used as the optical fiber 3 at the output end 1 f of the light collector 1. Connected.

  The connection between the exit end 1f of the light collector 1 and the incident end of the optical fiber 3 was welded by heating the fiber end, and the outer periphery was closely fixed by a support fixing holder. In addition, you may contact | connect tightly through the translucent epoxy adhesive to the connection part of the output end 1f of the light-condensing plate 1 with the optical fiber 3 end.

Two solar light collecting modules 10 using such a light collecting plate 1 were used and installed so that the X axis was in the east-west direction. A total of four optical fibers 3 were fixed to each light collector 1 by a fixing holder. The exit ends of the four optical fibers 3 were fixedly installed together on a dark room ceiling of about 6 tatami mats. About 500-1000 lm of light can be emitted per one optical fiber 3 that is actually irradiated with sunlight and connected to the solar condensing module 4, and it becomes 2000-4000 lm by using four of them. It was. Thereby, it was recognized that sufficient illuminance was obtained to illuminate a space of about 10 m ² , and the effectiveness of the solar light collecting module 4 could be confirmed.

1: Light collector
1a: reflection end side 1b: emission end side 1c: upper surface side 2: fiber connection part
3: Optical fiber
4: Condensing module 5: Panel mount 6: Lighting fixture 7: Lens condensing unit 8: Transparent dome 9: Solar position detection sensor 10: Tracking mount

Claims (5)

  A transparent plate-like light collecting plate, on the back surface of the light collecting plate, a plurality of inclined surfaces for reflecting sunlight incident from the front surface in the direction of the light collecting region on one side surface are arranged in parallel in the direction of the light collecting region. And a light collecting plate which is provided by changing the inclination angle between the adjacent inclined surfaces and which is provided in a curved shape centering on the light collecting region. Light condensing module.   2. The solar light collector according to claim 1, wherein the inclined surface is a curved surface convex toward the outside of the light collector in a cross section orthogonal to the inclined surface and parallel to the thickness direction of the light collector. Optical module.   The curvature of the curved surface in the cross section orthogonal to the inclined surface of the inclined surface and parallel to the thickness direction of the light collector is equal to the curvature of the curved surface centered on the light collecting region. Solar condensing module.   The solar light collecting module according to any one of claims 1 to 3, wherein a height of the inclined surface is lowered toward the light collecting region.   A solar light collecting panel, wherein a plurality of the solar light collecting modules according to claim 1 are juxtaposed on a gantry.