JP4587395B2 - Irradiation head - Google Patents

Description

  The present invention relates to an irradiation head in an illuminating device, and more particularly to an irradiation head including a diffusion plate for converting light emitted from a planar light source.

2. Description of the Related Art Conventionally, there is known an irradiation head in which a light source in which LED element groups are arranged in a plane, a diffusion plate, and the like are built in a housing (housing) (see, for example, Patent Document 1). Inside the head, as shown in FIG. 1 or FIG. 5 of the document 1, a diffusion plate (5) or (8) as a translucent diffusing means is fixed at one point with respect to the light source (1). Are arranged in parallel with the separated distance.

By the way, in a lighting device equipped with such an irradiation head, the irradiation distance from the light source to the irradiation object, so-called work distance, is limited to some extent from the viewpoint of satisfying the required light characteristics.
This means that the above-mentioned separation distance is also fixed at a distance that allows uniform irradiation while maintaining the illuminance of the light source as much as possible with respect to the irradiation object. On the other hand, this work distance varies depending on the size of the irradiation object and the installation environment of the irradiation head. Therefore, the illumination device in which the work distance is fixed at one point has a drawback that it is impossible to ensure illuminance maintenance and uniform irradiation in response to the change in the work distance.

Of course, in order to obtain uniform irradiation light according to changes in the work distance while maintaining the illuminance, it is only necessary to have several types of irradiation heads corresponding to various work distances. However, on the other hand, considering the purchase cost of the irradiation head, the storage space, and the replacement operation of the irradiation head, a great disadvantage is highlighted.

As described above, the conventional irradiation head has an inherent problem that it cannot cope with a change in work distance. This problem becomes more serious when the CCD camera is used as the irradiation light receiving element because it leads to variations in received signals or lowers the level of received signals, compared to the case of receiving light with the naked eye.

JP 2003-65960 A

Accordingly, an object of the present invention is to provide an irradiation head that can cope with a situation in which the work distance is changed, and can simultaneously maintain illuminance maintenance and uniform irradiation.

According to the present invention, the above-described problem is that the diffusion from the light source in the housing containing the planar light source and the diffusion plate facing the planar light source according to the irradiation distance from the light source to the irradiation object. The problem is solved by providing a double mechanism that can adjust the distance between the plates and detachably fix the plates.

According to the present invention, the following remarkable effects are exhibited.
(1) Although the unit is a single unit, the distance between the diffuser plates can be adjusted according to the change in the work distance, so that uniform irradiation light can be obtained without fear of light quantity loss.
(2) The diffusion plate mounted on the unit (1) can be easily replaced with a diffusion plate having a different diffusion coefficient. For the newly installed diffusion plate, the distance between the diffusion plates can be adjusted according to the change in the work distance, as in (1).
(3) If necessary, a plurality of diffusion plates can be easily used by simply adding another diffusion plate to the unit on which the diffusion plate is mounted.
(4) Preparation and storage / maintenance of several types of irradiation heads corresponding to various work distances, and frequent replacement work of irradiation heads are omitted, which is extremely economical.

Hereinafter, an example of an irradiation head of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a partially broken perspective view showing an example of an irradiation head according to the present invention.
FIG. 2 is a perspective view showing the positional relationship among the planar light source, the diffusion plate, and the irradiation object.
FIG. 3 is a partially enlarged perspective view of the inner wall surface of the end portion of the housing.
FIG. 4 is a perspective view showing one embodiment of temporary fixing of the slide plate by the pole plunger.
FIG. 5A is a schematic perspective view showing another aspect of the irradiation head according to the present invention.
FIG. 5B is a partial plan view of FIG.
FIG. 5C is a partial perspective view of the inside of FIG.

FIG. 1 shows an example of a vertical irradiation head. FIG. 1 itself is a perspective view showing a state in which the right side portion of the front lateral plate (4b) is broken toward the figure, as will be described later. In the figure, (1) is a planar light source, (2) is a mounting substrate for the planar light source (1), (3) is a diffuser plate, and (4) is a planar light source (1) and a diffuser plate (3). ). Here, the planar light source (1) and the diffusion plate (3) are arranged in parallel at a desired separation distance (L) as shown in FIG. Further, (S) is an irradiation object (surface to be irradiated), and (D) is a distance from the diffusion plate (3) closest to the irradiation object to the irradiation object (S), that is, a work distance. In addition, this work distance (D) may be a distance from the irradiation head to the irradiation object (S).
In the present invention, the housing (4) including the planar light source (1) and the diffusion plate (3) can adjust the separation distance (L) according to the irradiation distance from the light source to the irradiation object. In addition, a double mechanism capable of detachably fixing the diffusion plate is provided, and this mechanism will be described.

The housing (4) is composed of a bottom plate (4a), opposed horizontal plates (4b), side plates (4c), and a slide plate (4d), and is open on the upper side (irradiated object or irradiated surface side). A rectangular parallelepiped space is formed. Further, (5) and (6a) to (6d) are grooves provided on the three side walls of the casing (4) in parallel with the surface of the bottom plate (4a). (7) is a slide groove provided at the end (left end in the figure) of the opposite horizontal plate (4b) orthogonal to the grooves (5) and (6a) to (6d). Therefore, the groove structure of the opposing horizontal plate (4b) is plane symmetric.

Here, the three ends of the mounting substrate (2) of the planar light source (1) are fitted into the groove (5). The mounting substrate (2) itself may be fixed to the bottom plate (4a) by another fixing means. On the other hand, three end portions of the diffusion plate are detachably inserted into any of the grooves (6a) to (6d). That is, the diffusion plate (3) is inserted into any of the grooves (6a) to (6d) in response to the change in the work distance (D). By this position change, the separation distance (L) is adjusted, and as a result, the specification conforms to the change of the work distance. Such adjustment of the separation distance (L) is not limited to the already installed diffusion plate (3), and is also applied when the plate is replaced with a diffusion plate having another diffusion coefficient. When the position of the diffusion plate (3) is changed or replaced, the slide plate (4d) is pulled up above the housing (4). Thereafter, the slide plate (4d) is moved along the slide groove (7) to the bottom plate. (4a) The surface is lowered to the surface, and the diffusion plate (3) and the mounting substrate (2) are fixed at their end surfaces. At that time, if necessary, as shown in FIG. 4, the ball plunger (8) may be inserted into the horizontal plate (4 housing) at both lower corners of the slide plate (4d) and temporarily fixed. Good.

As is clear from the above, what is characteristic of the present invention is that the diffusion distance (L) of the diffusion plate (3) that can cope with the change of the work distance (D) in a single irradiation unit. And a dual mechanism for detachably fixing the plate is provided.

In the present invention, the planar light source is formed by two-dimensionally arranging light bulb groups and LED element groups. As the LED element, various types of commercially available specifications such as an LED capable of obtaining a standard amount of light and a high luminance type are adopted. When LED elements are used, about 20 to 1000 of them may be fixed on the mounting substrate (2). On the other hand, the diffusion plate (3) has a function of diffusing incident light from the planar light source (1) in all directions without directivity, and is an important element in the present invention. The diffusing plate (3) is a glass substrate or a resin substrate such as an acrylic resin having one or both surfaces provided with irregularities or a pigment, and has a diffusion coefficient of about 0.2 to 0.95 and 15% to 90%. Those having a transmittance of about% are preferred. The separation distance (L) is usually adjusted intermittently or continuously in the range of 0 mm to 200 mm. The grooves (5), (6a) to (6d), and (7) may be made to correspond to the thicknesses of the mounting substrate (2), the diffusion plate (3), and the slide plate (4d), respectively. Moreover, about groove | channel (6a)-(6d), the space | interval between grooves should just be about 5 mm-100 mm.

In the embodiment of FIG. 1, a single diffusion plate is used. However, in this aspect, diffusion plates having the same diffusion coefficient may be used in combination, or a plurality of diffusion plates having different diffusion coefficients may be used in combination. Thereby, illuminance maintenance and uniform irradiation are realized with high accuracy. This is particularly significant when the planar light source (1) composed of LED element groups is employed. As is well known, a portion where light is interrupted (“dark phenomenon”) occurs between adjacent LED elements. However, this dark place phenomenon is eliminated by using a plurality of diffusion plates according to the present invention, and not only the light quantity loss of the light source is eliminated, but also the irradiation light is made more uniform. Each diffusion plate employs a diffusion coefficient of about 0.2 to 0.95 and a transmittance of about 15% to 90%.

By the way, in the aspect of FIG. 1, fixation of a diffusion plate (3) is an intermittent fixing system. However, in another aspect of the present invention, the separation distance (L) may be continuously adjusted by slidably installing the diffusion plate (3) together with the planar light source (1) as necessary. it can. An example in which such a slide method adopts a horizontal irradiation head is shown in FIGS. 5 (a) to 5 (c).

In the embodiment shown in FIG. 5A, first, the diffusing plate (3) can be freely put in and out with the openable top cover (4d) on the upper surface of the housing (4) opened. (9) is a hinge, and (10a) and (10b) are clip (rack) members. And the mechanism which made the diffuser plate (3) slidable along the light emission direction inside the housing (4) is shown. Therefore, in this figure, the left side surface of the housing (4) toward the drawing is the surface of the irradiation object (S) shown in FIG.

Further, (11) is a slit formed along the horizontal plate (4b), (12) is a knob with a screw lock (stopper), (13) is a mandrel (screw), and the knob (12) is clockwise. It is screwed. (14) is an L-shaped bracket fixed by screwing the tip of the mandrel (13), and (15) is a guide rail for suspending the L-shaped bracket (14). One side of the L-shaped mold (14) is provided in parallel with the inner wall of the horizontal plate (4b), and therefore the other side is in an overhanging state. The above members are provided on the opposite horizontal plate (4b) as a surface object. At this time, the diffusion plate (3) is provided on each side of the L-shaped metal fitting (14) protruding from both inner walls of the horizontal plate (4b). Is screwed.

The above state is shown in FIG. 5 (b) as a plan view of the fixed state of the diffusion plate (3) viewed from the top of the housing (4), and in FIG. The fixed state of 3) is as shown as a perspective view seen from the inside of the housing (4). In these figures, (16) is a screw for fixing the diffusion plate (3).

5 (a) to 5 (c), the diffusion plate (3), the knob (12), the mandrel (13) and the L-shaped metal fitting (14) are integrally coupled. Therefore, when the knob (12) is pulled toward the planar light source (1) or the irradiation object (S), the mandrel (13) moves along the slit (11), and accordingly, the diffusion plate (3 ) Also move. At this time, since the L-shaped mold (14) for fixing the diffusion plate (3) is suspended on the guide rail (15) and slides on the guide rail (15), the surface movement of the diffusion plate (3) proceeds smoothly. . In this way, by pulling the knob (12) toward the planar light source (1) or the irradiation object (S), the separation distance (L) continuously decreases or increases, so that the work distance (D) High-accuracy response to changes is realized.

Next, a method for replacing the diffusion plate (3) will be described with reference to FIG. In order to replace the diffuser plate (3) with another diffuser plate, first, the two tabs (12) outside the horizontal plate (4b) are turned counterclockwise to be removed from the mandrel (13). Next, the clip members (10a) and (10b) are removed, and the mandrel (13) is removed from the slit (11) with the openable top cover (4d) on the top surface of the housing (4) opened. The diffuser plate (3) integrally coupled with the L-shaped metal fitting (14) is pulled up above the housing (4) and taken out to the outside. Thereafter, the diffuser plate is replaced with another diffuser plate integrally coupled with the L-shaped metal fitting (14), and the other diffuser plate is disposed in the housing (4) in the reverse order. At this time, if it is necessary to adjust the separation distance (L), it may be adjusted by the procedure described above.

  The modes of FIGS. 5A to 5C develop into various modifications. If two or more sets of the slide type diffusion plates (3) are incorporated, the two or more diffusion plates can be used together, as in the embodiment of FIG. Further, a diffusion plate whose position is fixed is provided in a space facing the irradiation object of the housing (4), and a slide type diffusion plate (3) is disposed between the diffusion plate and the planar light source. Is also useful. In fixing the position of the diffusion plate in this case, the groove method shown in FIG. 1 may be adopted. Furthermore, if the mounting substrate (2) of the planar light source (1) is also deformed from the fixed method to the slide method, the degree of freedom in adjusting the separation distance (L) is significantly improved.

Since the irradiation head of the present invention has a uniform irradiation effect without reducing the amount of light even when the work distance changes, it can be used for product display other than image processing illumination, indoor illumination, or medical use. Applied.

The partially broken perspective view which shows an example of the irradiation head which concerns on this invention. The perspective view which shows the positional relationship of a planar light source, a diffusion plate, and an irradiation target object. The partial expansion perspective view of the inner wall surface of a housing | casing edge part. The perspective view which shows the one aspect | mode of the temporary stop of the slide plate by a pole plunger. (A) is a schematic perspective view showing another aspect of the irradiation head according to the present invention, FIG. 5 (b) is a partial plan view of FIG. 5 (a), and (c) is FIG. 5 (a). FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surface light source 2 Mounting substrate 3 of surface light source (1) Diffusion plate 4 Case 4a Bottom plate 4b Horizontal plate 4c Side plate 4d Slide plate 5 Mounting groove 6a-6d of a board | substrate (2) Insertion groove of a diffusion plate (3) 7 Slide groove
8 Ball plunger 9 Hinge 10 Clip 11 Slit 12 Knob with screw lock (stopper) 13 Mandrel 14 L-shaped mold 15 Guide rail S Irradiation object D Work distance L Separation distance

Claims (2)

In an irradiation head mainly composed of a casing having a planar light source and a diffuser plate facing the light source at a predetermined separation distance, the diffusion is performed in the casing according to the irradiation distance from the light source to the irradiation object. An irradiation head characterized in that, by providing a double mechanism capable of adjusting the distance between the plates and detachably fixing the plates , illuminance maintenance and uniform irradiation can be secured at the same time .
The mechanism is a mechanism in which grooves for fitting the end portions of the three sides of the diffusion plate are formed in multiple stages on the inner wall surface of the housing, and the diffusion plate can be freely inserted and removed through one side surface of the housing. The irradiation head according to claim 1.

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