JP5131807B2 - Solar radiation sensor - Google Patents

Description

  The present invention relates to a solar radiation sensor used for detecting the incident direction of sunlight.

As a prior art, in a method for realizing a sun visor device for an automobile, configurations and means necessary for detecting a sunlight position are described in claims 4 to 6 of Patent Document 1. For example, according to the configuration and means, sunlight incident on the sensor through the Fr glass is incident on a light receiving window portion having a diameter d constituting the sensor, and sunlight having a diameter d is projected onto the light receiving surface. The The light receiving surface is divided into four parts, and it is possible to obtain an output corresponding to the incident state of sunlight by performing arithmetic processing based on signals obtained from the respective light receiving elements.
JP 2003-159942 A

The problem with the structure of the known example described in Patent Document 1 is concerned that the incident direction detection accuracy deteriorates due to ambient light, which may be a major restriction on the system. Therefore, in order to eliminate the disturbance light as described above, the applicant considered to devise the shape of the signal introduction path until the incident light reaches the light receiving sensor, and made a prototype and conducted an experiment. As a result, in fact, the ultraviolet component contained in sunlight is mainly refracted into disturbance light and reaches the light receiving sensor, which has a great influence on the incident angle detection accuracy. found.
This invention is made | formed in view of the said situation, The objective is to provide the solar radiation sensor which can exclude the influence by disturbance light.

According to the solar radiation sensor of Claim 1, the light- receiving path formed with the light- shielding wall which restrict | limits the incident angle of sunlight ,
A light receiving window that is disposed on the terminal end side of the light receiving path and is configured to have a smaller opening area than the light receiving path and determine a light receiving area;
Sunlight received through the light receiving window, in which and a detectably configured light sensing unit the difference in received light intensity in each region obtained by dividing the light receiving area into a plurality,
By transmitting a part of the infrared light component and the visible light component included in the sunlight to be incident on the light receiving sensor section via the receiving path, characterized in that it comprises an optical filter means to remove the ultraviolet component.
With such a configuration, the incident angle of sunlight that attempts to reach the light receiving region through the light receiving window is limited by the length of the light receiving path and the difference in opening area between the light receiving path including the light shielding wall and the light receiving window. The And since an optical filter means removes the ultraviolet component of sunlight, the influence of a disturbance can be excluded.

And since an optical filter means is provided with the characteristic which permeate | transmits the infrared component which sunlight has, it can detect an incident direction with the received light intensity based on an infrared component.

The optical filter means, since includes a characteristic part also transmits the the visible light component that Yusuke sunlight, not infrared light component only, to detect the incident direction also in addition received light intensity based on the visible light component Can do.

According to the solar radiation sensor of claim 2 to 4, wherein the optical filter means, specifically, so as to cover the starting end side of the light receiving path (Claim 2), so as to cover the light receiving window at the inside of the light receiving path to (claim 3), since the arrangement (claim 4) between the light receiving window and the light receiving sensor unit, both can be reliably removed ultraviolet component.

According to the solar radiation sensor of claim 5 , the light receiving path member formed by surface mounting the light receiving sensor section on the printed circuit board and integrally forming the light receiving path, the light receiving window and the optical filter means is provided from above the light receiving sensor section. And it attaches on a printed circuit board so that a bottom side may contact the surface side of the said light reception sensor, and it fixes by screwing . Therefore, the assembling property of the solar radiation sensor is improved.

According to the solar radiation sensor of the present invention, the optical filter means transmits part of the infrared ray component and visible ray component of sunlight, and eliminates the main influence of disturbance by removing the ultraviolet ray component, so that the incident direction of sunlight. Can be detected with higher accuracy.

(First embodiment)
A first embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a (a) plan view, (b) a longitudinal front view, and (c) a side view of a solar radiation sensor. A light receiving sensor (light receiving sensor unit) 12 is surface-mounted on the printed board 11, and a light receiving path member 13 is attached from above the light receiving sensor 12. The light receiving path member 13 includes a quadrangular light receiving path 15 formed of a space surrounded by four light shielding walls 14 (a, b, c, d). 1 (b) is a bottom surface portion 17 in which a light receiving window 16 having a small opening area is formed in the central portion. That is, the light incident on the light receiving path 15 from above in FIG. 1B reaches the light receiving surface 12S of the light receiving sensor 12 through the light receiving window 16.
The light receiving surface 12S is divided into four light receiving regions in accordance with the center line shown in FIG. 1A, and the light receiving intensity in each of the divided regions can be detected independently. Therefore, the incident direction of sunlight incident on the light receiving path 15 can be detected by detecting the difference in received light intensity between these four regions.

  An attachment step 18 having an extremely shallow step is formed on the start end side of the light receiving path 15. An ultraviolet cut filter (optical filter means) 19 is press-fitted and fitted to the attachment step 18 from above. (Adhesive may be used if necessary). The ultraviolet cut filter 19 is formed so as to block the transmission of ultraviolet rays using, for example, a resin, glass, or the like as a base material, and is one or more kinds consisting of a group of Al, Si, Ti, V, Cr, Mn, Fe, and the like. A thin film of zinc oxide containing a very small amount of the above metal element is formed by vapor deposition or sputtering on a substrate.

  Attachment portions 20a and 20b are formed on both outer sides of the light shielding walls 14a and 14b. The mounting portions 20a and 20b are provided with screw holes from the lower side in FIG. 1B, and the screws 21a and 21b are screwed from the back surface of the printed board 11 through the mounting holes formed in the board 11. The light receiving path member 13 is fixed to the printed board 11 by being inserted. The solar radiation sensor 22 is comprised by the above.

Next, the operation of this embodiment will be described. The incident angle of sunlight incident on the light receiving path 13 of the solar radiation sensor 22 is limited according to the dimensions of the light shielding wall 14 and the light receiving window 16. From the center of the light receiving sensor 12, only light having an incident angle within a region connecting the end of the light receiving path 13 and the light receiving window 16 is received through the light receiving window 16 as indicated by a broken line in FIG. It reaches the light receiving surface 12S of the sensor 12. When entering the light receiving path 13, the ultraviolet rays contained in the sunlight are blocked by the ultraviolet cut filter 19, so that some of the other infrared and visible light components are transmitted and received by the light receiving sensor 12. Is done.
Then, the received light intensity for each light receiving area detected and output by the light receiving sensor 12 is output to a control circuit (not shown), and the magnitude of the received light intensity of each area is compared. The incident direction of sunlight with respect to the direction in which the center is directed is detected.

  As described above, according to the present embodiment, the ultraviolet ray cut filter 19 is disposed on the start end side of the light receiving path 15 and the ultraviolet ray component is removed from the sunlight received by the light receiving sensor 12 of the solar radiation sensor 22. The influence of disturbance can be eliminated, and the incident direction of sunlight based on the detection output of the light receiving sensor 12 can be detected with higher accuracy than before. The solar radiation sensor 22 includes a light receiving sensor 12 mounted on the printed circuit board 11, and a light receiving path member 13 formed integrally with the light receiving path 15, the light receiving window 16, and the ultraviolet cut filter 19 from above the light receiving sensor 12. Since it attaches and fixes on the printed circuit board 11, the assembly property of the solar radiation sensor 22 becomes favorable.

(Second embodiment)
FIG. 2 shows a second embodiment of the present invention. The same parts as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted. Only the different parts will be described below. In the solar radiation sensor 23 of the second embodiment, the shape of the light receiving path member 24 is slightly different, and the mounting step 18 as in the first embodiment is not formed on the start end side of the light receiving path 15. Instead, the bottom surface portion 17 is formed with a mounting convex portion 25 that surrounds the periphery of the light receiving window 16 in a rectangular shape. An ultraviolet cut filter (optical filter means) 26 is press-fitted and fitted inside the mounting convex portion 25.

  According to the second embodiment configured as described above, since the ultraviolet cut filter 26 is disposed inside the light receiving path 15, the ultraviolet component of sunlight that is about to enter the light receiving sensor 12 through the light receiving window 16 is reduced. It can be removed in the same manner as in the first embodiment. Further, the size of the ultraviolet cut filter 26 can be made smaller than that in the first embodiment.

(Third embodiment)
FIG. 3 shows a third embodiment of the present invention, and only parts different from the first embodiment will be described. In the solar radiation sensor 27 of the third embodiment, the shape of the light receiving path member 28 is slightly different, and the mounting step portion 18 as in the first embodiment and the mounting convex portion 25 as in the second embodiment are formed. Absent. Instead, a recess 29 is formed on the side where the bottom surface portion 17 faces the light receiving sensor 12. The concave portion 29 is provided in order to form a space for arranging the ultraviolet cut filter (optical filter means) 30 between the main body portion 12B surrounding the light receiving surface 12S of the light receiving sensor 12 and the bottom surface portion 17.

That is, when assembling the solar radiation sensor 27, after the light receiving sensor 12 is mounted on the printed circuit board 11, the ultraviolet cut filter 30 is placed above the main body 12B, and the ultraviolet cut filter 30 is placed in the recess 29 from above. In this manner, the light receiving path member 28 is covered and screwed and fixed from the back side of the substrate 11 as in the first embodiment. As a result, the ultraviolet cut filter 30 is held between the light receiving window 16 and the light receiving sensor 12.
According to the third embodiment configured as described above, since the ultraviolet cut filter 30 is disposed between the light receiving window 16 and the light receiving sensor 12, the sun that is about to enter the light receiving sensor 12 through the light receiving window 16 is used. The ultraviolet component of light can be removed as in the first embodiment.

The present invention is not limited to the embodiments described above and shown in the drawings, and the following modifications or expansions are possible.
Light receiving sensor unit is not limited to quartering the one light receiving area of the sensor as the light receiving sensor 12, it may be divided into two or three or more divisions in accordance with the design specifications. Further, a plurality of light receiving sensors may be arranged to detect the light receiving intensity of each sensor individually.
The cross-sectional shape of the light receiving path and the shape of the light receiving window may be circular.

It is 1st Example of this invention, (a) Top view of a solar radiation sensor, (b) Longitudinal front view, (c) Side view FIGS. 1A and 1B are diagrams showing a second embodiment of the present invention. FIG. 1B equivalent view showing a third embodiment of the present invention.

Explanation of symbols

  In the drawings, 11 is a printed circuit board, 12 is a light receiving sensor (light receiving sensor), 12S is a light receiving surface, 13 is a light receiving path member, 14 is a light shielding wall, 15 is a light receiving path, 16 is a light receiving window, and 19 is an ultraviolet cut filter ( Optical filter means), 22 and 23 are solar radiation sensors, 24 is a light receiving path member, 26 is an ultraviolet cut filter (optical filter means), 27 is a solar radiation sensor, 28 is a light receiving path member, and 30 is an ultraviolet cut filter (optical filter means). Indicates.

Claims (5)

A light receiving path formed by a light blocking wall that limits the incident angle of sunlight ;
A light receiving window that is disposed on the terminal end side of the light receiving path and is configured to have a smaller opening area than the light receiving path and determine a light receiving area;
In a solar radiation sensor comprising sunlight received through this light receiving window and a light receiving sensor unit configured to be able to detect a difference in received light intensity in each region obtained by dividing the light receiving region into a plurality of regions,
Solar radiation sensor, characterized in that it comprises the by transmitting a portion of the infrared component and a visible light component sunlight has tries incident on the light receiving sensor unit, optical filter means to remove the ultraviolet component through the light path . 2. The solar radiation sensor according to claim 1, wherein the optical filter means is disposed so as to cover a start end side of the light receiving path . Said optical filter means, solar radiation sensor of claim 1, wherein the inside of the light receiving path is disposed so as to cover the light receiving window. It said optical filter means, solar radiation sensor of claim 1 Symbol mounting, characterized in that it is disposed between the light receiving window and said light receiving sensor unit. The light receiving sensor part is surface-mounted on a printed circuit board,
A light receiving path member formed by integrally forming the light receiving path, the light receiving window, and the optical filter means is mounted on the printed circuit board from above the light receiving sensor unit so that the bottom side is in contact with the surface side of the light receiving sensor. solar radiation sensor according to any one of claims 1 to 4, characterized in that fixed by screws Te.

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