JP3841929B2 - Imaging position adjustment structure of virtual switch - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a so-called virtual switch that can display image information such as characters and figures drawn on a translucent image sheet as an upright real image at a position away from the image sheet. The present invention relates to a structure capable of adjusting an imaging position.
[0002]
[Prior art]
Unlike conventional mechanical switches in which an operator directly touches keys and buttons with a finger, a virtual switch activates a sensor when a finger is brought close to an image formed in space, thereby switching ON / OFF. This switch is capable of performing hygiene because it is not necessary to touch the device directly, and is used as a switch for medical devices in hospitals where hospital infection has recently become a problem, or for flushing public toilets. Very large demands are expected as switches and in various other fields.
[0003]
An example of such a virtual switch is shown in FIG.
In the figure, a virtual switch 41 has a cylindrical casing 42 that opens upward, and a surface light source (backlight) 43 composed of an LED, an EL, or the like is disposed at the bottom of the casing 42. Has been.
[0004]
Above the surface light source 43, a translucent image sheet (name plate) 44 on which image information such as characters and figures is drawn is arranged. A lens unit 45 for forming the image information displayed on the nameplate 44 as an erect real image A in the upper opening of the housing 42 is provided further above the nameplate 44. The lens unit 45 is configured by closely attaching a large number of gradient index microlens elements and bonding them with an adhesive.
[0005]
A photoelectric switch 46 including a light projecting unit 46a and a light receiving unit 46b disposed to face the light projecting unit 46a is provided in the upper opening of the housing 42. Although not shown, the photoelectric switch 46 is electrically connected to a drive circuit and an output circuit for turning on / off the surface light source 43.
[0006]
In the virtual switch having such a configuration, when the surface light source 43 is in the ON state, the light emitted from the surface light source 43 is irradiated to the lens unit 45 through the name plate 44, and the lens unit 45 causes the name plate 44 to emit light. The upper image information is imaged as an erect real image A (for example, the English character “ON”) in the upper opening of the housing 42.
[0007]
From this state, when the operator puts a finger into the upper opening of the housing 42 and touches the erect real image A, the light emitted from the light projecting portion 46a of the photoelectric switch 46 is blocked by the finger, The drive circuit is activated and the surface light source 43 is turned off.
[0008]
Conversely, when the operator puts a finger into the upper opening of the housing 42 when the surface light source 43 is in the OFF state, the light emitted from the light projecting portion 46a of the photoelectric switch 46 is blocked, and as a result, the drive circuit , The surface light source 43 is turned on, and the erect real image A is displayed again.
[0009]
[Problems to be solved by the invention]
The lens unit used in such a virtual switch generally has a large difference in refractive index due to a difference in wavelength (that is, due to chromatic aberration). Therefore, when the backlight is replaced with one of different color light, The image formation position of the image changes depending on the color light.
[0010]
For example, when the SELFOC lens (trade name) SLA-20B manufactured by Nippon Sheet Glass Co., Ltd. is used, when the theoretical lens length is Z = 6.0 (mm), the red light (wavelength λ = 660 nm) is used. The imaging distance is 24.8 (mm), the imaging distance for green light (wavelength λ = 570 nm) is 16.0 (mm), and there is a difference of 8.8 (mm) between them. is there. Further, in the case of red light and blue light (wavelength λ = 450 nm), the difference is further increased.
[0011]
Therefore, for example, in a virtual switch using a red light backlight, when the backlight is changed to a green light, the image formation position of the image is shifted by 8.8 (mm) toward the lens unit (that is, the back of the aperture). . From this state, when the operator puts a finger into the opening in order to touch the image, the photoelectric switch is activated before the finger touches the image. Due to the deviation from the detected position, the operator feels uncomfortable.
[0012]
Therefore, it is conceivable to use a lens unit in which chromatic aberration is corrected so that the image of each color light is formed at a substantially constant position (that is, the detection position of the photoelectric switch). Since the lens unit itself corrected for chromatic aberration is very expensive, the cost of the entire product is greatly increased.
[0013]
The present invention has been made in view of such a conventional situation, and provides an imaging position adjustment structure for a virtual switch that can inexpensively and easily form an image at a fixed position regardless of the type of color. The purpose is to do.
[0014]
[Means for Solving the Problems]
The imaging position adjustment structure of the virtual switch according to the invention of claim 1 allows light emitted from a surface light source to pass through a translucent image sheet in the casing, and image information of the image sheet is transmitted to the casing by a lens unit. In an imaging position adjustment structure of a virtual switch that forms an image at or near a body opening and switches on and off of the surface light source based on a detection signal from a photoelectric switch provided in the housing A plurality of grooves for detachably holding the lens unit and the image sheet are formed in the optical axis direction inside the housing, and the image information of the image sheet is connected by the lens unit. Depending on the color type of the surface light source so that the image position matches the detection position of the photoelectric switch, regardless of the color type of the surface light source. The combination of the grooves to be held serial lens unit and the image sheet respectively is characterized in that it is implemented more than once.
[0015]
The imaging position adjusting structure for a virtual switch according to a second aspect of the present invention is the virtual switch imaging position adjusting structure according to the first aspect, wherein at least one of the lens unit or the image sheet is held by a holding body, A protrusion that can be engaged with the groove is formed.
[0016]
According to a third aspect of the present invention, in the imaging position adjusting structure of the virtual switch according to the second aspect, the protrusion is disposed at a position shifted from a center line in a direction orthogonal to the optical axis direction of the lens unit or the image sheet. It is characterized by having.
[0017]
According to a fourth aspect of the present invention, there is provided the imaging position adjusting structure for a virtual switch according to the first aspect, wherein the groove is spaced apart from the first and second opposing inner wall surfaces in the housing by a predetermined distance in the optical axis direction. It is characterized by being arranged opposite each other.
[0018]
The imaging position adjusting structure for a virtual switch according to a fifth aspect of the present invention is the virtual switch imaging position adjusting structure according to the first aspect, wherein the grooves are spaced apart from each other in the optical axis direction on the first and second opposing inner wall surfaces in the casing. The first and second grooves arranged opposite to each other and the third and fourth opposite inner wall surfaces different from the first and second opposite inner wall surfaces are opposed to each other at a predetermined interval in the optical axis direction. In addition, the optical axis direction position includes the third and fourth grooves shifted from the first and second grooves by ½ pitch.
[0019]
The imaging position adjusting structure of the virtual switch according to the invention of claim 6 is characterized in that, in claim 1, the groove is a spiral groove formed in a spiral shape on the inner peripheral surface of the casing.
[0020]
According to the present invention, the light emitted from the surface light source passes through the image sheet and irradiates the lens unit, and the lens unit forms image information on the image sheet at or near the opening of the housing. .
[0021]
From this state, when the operator puts a finger into the opening of the housing and touches the image with the finger, the photoelectric switch is activated, and the surface light source is switched on / off by receiving the detection signal of the photoelectric switch. .
[0022]
Next, when the color of the surface light source is changed, the groove of the housing is appropriately selected according to the wavelength of the color, and the positions of the lens unit and the image sheet in the optical axis direction are adjusted.
[0023]
For example, when the color of the surface light source is changed from red to green, the lens unit is moved to the groove near the housing opening, and the image sheet is moved to the groove near the lens unit away from the surface light source. As a result, an image can be formed at the same image formation position as when the surface light source is red.
[0024]
In this case, since the imaging position is adjusted using the groove formed in the housing, it is possible to inexpensively and easily form an image at a fixed position regardless of the type of color. become.
[0025]
It is preferable that at least one of the lens unit and the image sheet is held by a holding body having protrusions that can be engaged with the grooves of the housing.
[0026]
It is preferable that the protrusion of the holding body is disposed at a position shifted from the center line in the direction orthogonal to the optical axis direction of the lens unit or the image sheet. In this case, by attaching the holding body upside down and attaching it to the groove, the position of the lens unit or the image sheet in the optical axis direction can be adjusted for a distance smaller than the groove pitch p. . That is, in this case, fine adjustment of the imaging position is possible.
[0027]
It is preferable that the grooves are arranged to face each other at a predetermined interval in the optical axis direction on the first and second opposing inner wall surfaces in the housing.
[0028]
The grooves include first and second grooves disposed opposite to each other at a predetermined interval in the optical axis direction on first and second opposed inner wall surfaces in the housing, and first and second opposed inner wall surfaces, Different third and fourth opposing inner wall surfaces are arranged opposite to each other at a predetermined interval in the optical axis direction, and the positions in the optical axis direction are shifted by 1/2 pitch from the first and second grooves. It is preferable to have 4 grooves.
[0029]
In this case, when adjusting the position of the lens unit and the image sheet in the optical axis direction, by using the third and fourth grooves in addition to the first and second grooves, a ½ pitch can be obtained. Fine adjustment is possible.
[0030]
The groove is preferably a spiral groove formed in a spiral shape on the inner peripheral surface of the housing. In this case, fine adjustment at a finer pitch can be performed.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[First Embodiment]
1 to 5 are views for explaining an imaging position adjusting structure of a virtual switch according to the first embodiment of the present invention. FIG. 1 is a schematic vertical sectional view of the virtual switch, and FIG. FIG. 3 is an enlarged longitudinal sectional view of the lens assembly, FIG. 4 is a plan view of the lens assembly, and FIG. 5 is a partial sectional view taken along the line VV of FIG.
[0032]
As shown in FIGS. 1 and 2, the virtual switch 1 has a rectangular tube-shaped housing 2 that opens upward. A surface light source 3 composed of an LED (light emitting diode), an EL (electroluminescence), or the like is disposed at the lower portion of the housing 2.
[0033]
Above the surface light source 3, a translucent image sheet (name plate) 4 on which image information such as characters and figures is drawn is arranged. The transmitted light from the nameplate 4 is irradiated above the nameplate 4 and the image information drawn on the nameplate 4 is imaged as an upright real image A at or near the opening of the housing 2. A lens assembly 5 is provided. Note that the marking plate 4 and the lens assembly 5 indicated by solid lines in FIG. 1 respectively indicate the arrangement of the surface light source 3 with a red color.
[0034]
A photoelectric switch 8 is provided in the opening of the housing 2. The photoelectric switch 8 includes a light projecting unit 8a that emits light such as infrared rays, and a light receiving unit 8b that is disposed to face the light projecting unit 8a and receives light emitted from the light projecting unit 8a. The light projecting / receiving portions 8a and 8b are connected to an external switching device (not shown), and when the light emitted from the light projecting portion 8a is blocked by the operator's finger, The ON / OFF state of the surface light source 3 can be switched.
[0035]
As shown in FIGS. 3 and 4, the lens assembly 5 includes a quadrangular prism-shaped lens unit 6 and a frame body 7 that holds the outer peripheral end face of the lens unit 6.
[0036]
The lens unit 6 is configured by closely attaching a large number of gradient index microlens elements and bonding them with an adhesive. In addition, as the lens unit 6, two sheet lenses formed by combining a large number of plano-convex microlens elements or biconvex microlens elements in a sheet shape, which are arranged to face each other at a predetermined interval, are used. You may do it. The frame body 7 is formed with opposing protrusions 7a.
[0037]
On the other hand, grooves 10 are formed on the opposing inner wall surfaces 2a and 2b (FIG. 2) of the housing 2 at a predetermined pitch p in the optical axis direction (vertical direction in FIG. 5). The grooves 10 on the inner wall surfaces 2a and 2b are arranged at positions facing each other, and the protrusions 7a of the frame body 7 of the lens assembly 5 are engaged with any of the grooves 10 facing each other.
[0038]
Although not shown, the nameplate 4 is also preferably held by a frame similar to the frame 7, and the projection of the frame is engaged with the groove on the inner wall surface of the housing 2. In addition, an openable / closable opening for attaching and detaching the lens assembly 5 and the nameplate 4 to the groove 10 is formed on the outer wall surface of the housing 2 (not shown).
[0039]
Next, the function and effect of this embodiment will be described.
The light emitted from the surface light source 3 passes through the marking plate 4 and is irradiated to the lens unit 6 of the lens assembly 5, and the lens unit 6 converts the image information on the marking plate 4 to the opening of the housing 2 or the vicinity thereof. The image A is imaged at the position S.
[0040]
From this state, when the operator puts a finger into the upper opening of the housing 2 and touches the image A, the photoelectric switch 8 is activated, receives a detection signal from the photoelectric switch 8 and receives a switching device (not shown). The surface light source 3 is switched on and off.
[0041]
Next, when the color of the surface light source 3 is changed from red to green, the lens assembly 5 and the nameplate 4 are removed from the groove 10 and inserted into the upper groove 10 (indicated by a one-dot chain line in FIG. 1). Lens assembly 5 'and nameplate 4'). As a result, an image of the green surface light source 3 can be formed at the position S of the upper opening, which is the same image formation position as when the surface light source 3 is red.
[0042]
Further, when the color of the surface light source 3 is changed from green to blue, the lens assembly 5 'and the name plate 4' are removed from the groove 10 and inserted into the upper grooves 10 respectively (two points in FIG. 1). Lens assembly 5 "and nameplate 4" shown by chain lines). Thereby, the image by the blue surface light source 3 can be imaged at the position S of the upper opening, which is the same image formation position as when the surface light source 3 is red.
[0043]
Thus, the direction in which the lens assembly 5 and the nameplate 4 are moved depends on the color, that is, the wavelength of the surface light source 3. When the color of the surface light source 3 is changed to one having a short wavelength, the lens assembly 5 and the nameplate 4 are moved into the groove 10 on the upper side (side approaching the upper opening), and conversely, the surface light source 3 When the color of the lens is changed to one having a long wavelength, the lens assembly 5 and the nameplate 4 are moved into the groove 10 on the lower side (side away from the upper opening).
[0044]
The moving distance of the lens assembly 5 and the name plate 4 is also set as appropriate according to the wavelength of the surface light source 3. In this example, it is possible to move a distance that is an integral multiple of the groove pitch p.
[0045]
As described above, according to the present embodiment, since the image forming position is adjusted using the grooves 10 formed in the opposed inner wall surfaces 2a and 2b of the housing 2, the color type of the surface light source 3 is adjusted. Regardless, it is possible to inexpensively and easily form an image at a fixed position. As a result, both the manufacturer side and the user side of the virtual switch can easily cope with the change of the color of the surface light source. In addition, the manufacturer can share the housing regardless of the type of color.
[0046]
[Second Embodiment]
FIG. 6 and FIG. 7 are diagrams for explaining an imaging position adjusting structure according to the second embodiment of the present invention. FIG. 6 is an enlarged longitudinal sectional view of the lens assembly, and FIG. 7 is a view for explaining the function and effect, corresponding to FIG. 5 of the first embodiment. In these drawings, the same reference numerals as those in the first embodiment denote the same or corresponding parts.
[0047]
In the first embodiment, as shown in FIG. 3, an example in which the center line m of the protrusion 7 a of the frame body 7 that holds the lens unit 6 coincides with the center line n of the lens unit 6 is shown. In the lens assembly 51 shown in the second embodiment, as shown in FIG. 6, the center line m of the projection 71 a of the frame 71 that holds the lens unit 6 is arranged at a position shifted from the center line n of the lens unit 6. The frame 71 is asymmetric with respect to the center line n. The deviation amount of the protrusion 71a is set to, for example, p / 4 (p: groove pitch).
[0048]
A state where the lens assembly 51 having such a configuration is engaged with a groove 10 in the housing 2 is shown by a solid line in FIG. Next, a state in which the lens assembly 51 is removed from the groove 10, turned upside down, and inserted into the same groove 10 is indicated by a two-dot chain line in FIG.
[0049]
Comparing the positions of these lens assemblies 51 and 51 ', it can be seen that both lens assemblies are displaced by p / 2. That is, in this case, the position adjustment of the lens unit 6 in the optical axis direction can be performed for p / 2 smaller than the pitch p of the groove 10, and the image forming position can be finely adjusted.
[0050]
[Third Embodiment]
In the first and second embodiments, the example in which the groove 10 is formed in the pair of opposed inner wall surfaces 2a and 2b in the housing 2 has been shown, but the application of the present invention is not limited to this, The groove 10 may be formed not only on the wall surfaces 2a and 2b but also on the other opposed inner wall surfaces 2c and 2d (see FIG. 2).
[0051]
In this case, as shown in FIG. 8 corresponding to the cross-sectional view taken along the line VIII-VIII of FIG. 2, the grooves 10 of the opposed inner wall surfaces 2c and 2d The position in the axial direction (vertical direction in FIG. 8) is shifted by p / 2. In FIG. 8, the right housing 2 is shown for convenience in order to compare the positions of the grooves 10 in the optical axis direction.
[0052]
When adjusting the image forming position, not only the grooves 10 of the opposed inner wall surfaces 2a and 2b but also the grooves 10 of the opposed inner wall surfaces 2c and 2d are used, as in the second embodiment, p / Fine adjustment of an integer multiple of 2 can be performed.
[0053]
[Fourth Embodiment]
In the first to third embodiments, an example in which a rectangular tube shape is used as the housing 2 and the facing groove 10 is formed on the facing inner wall surface in the housing 2 has been described. However, the present invention is not limited to this, and the casing 2 may be a cylindrical one, and a spiral groove may be formed on the inner peripheral surface of the casing 2. In this case, fine adjustment at a finer pitch can be performed by gradually screwing the lens assembly 5 and the name plate 4 when adjusting the imaging position.
[0054]
[Other application examples]
In each of the above-described embodiments, an example in which the present invention is applied to a virtual switch including a transmissive photoelectric switch has been described. However, the present invention is applicable to a virtual switch 1a including a reflective photoelectric switch as illustrated in FIG. The same applies to the above.
[0055]
9, the same reference numerals as those in FIG. 1 denote the same or corresponding parts, and here, the reflection type photoelectric switch 9 is configured by the light projecting unit 9a and the light receiving unit 9b arranged in the housing 2. .
[0056]
【The invention's effect】
As described above, according to the imaging position adjustment structure of the virtual switch according to the present invention, the imaging position is adjusted using the groove formed in the housing, so that the image can be displayed regardless of the type of color. There is an effect that it is possible to inexpensively and easily form an image at a certain position.
[Brief description of the drawings]
FIG. 1 is a schematic vertical sectional view of a virtual switch to which an imaging position adjusting structure according to a first embodiment of the present invention is applied.
FIG. 2 is a plan sectional view of the virtual switch (FIG. 1).
FIG. 3 is an enlarged longitudinal sectional view of a lens assembly constituting the virtual switch (FIG. 1).
FIG. 4 is a plan view of a lens assembly constituting a virtual switch (FIG. 1).
5 is a partial cross-sectional view taken along the line VV in FIG. 2;
FIG. 6 is an enlarged vertical cross-sectional view of a lens assembly constituting a virtual switch to which a second embodiment of the present invention is applied.
FIG. 7 is a diagram for explaining the function and effect of the second embodiment.
FIG. 8 is a view for explaining a third embodiment of the present invention and corresponding to a cross-sectional portion taken along line VIII-VIII in FIG. 2;
FIG. 9 is a schematic longitudinal sectional view showing a modification of the virtual switch to which the present invention is applied.
FIG. 10 is a schematic vertical cross-sectional view of a conventional virtual switch.
[Explanation of symbols]
1, 1a Virtual switch 2 Housing 2a, 2b Opposing inner wall surface 2c, 2d Opposing inner wall surface 3 Surface light source 4, 4 ', 4 "Inscription plate (image sheet)
5, 5 ′, 5 ″ Lens assembly 51, 51 ′ Lens assembly 6 Lens unit 7, 71 Frame (holding body)
7a, 71a Protrusions 8, 9 Photoelectric switch 10 Groove S Imaging position A Image p Pitch m, n Center line

Claims (6)

The light emitted from the surface light source in the housing is transmitted through the translucent image sheet, and the image information of the image sheet is imaged at or near the opening of the housing by the lens unit. In the imaging position adjustment structure of the virtual switch that switches the on / off state of the surface light source based on the detection signal from the provided photoelectric switch ,
Inside the casing, a plurality of grooves for detachably holding the lens unit and the image sheet are formed in the optical axis direction,
According to the color type of the surface light source so that the image formation position of the image information of the image sheet by the lens unit matches the detection position of the photoelectric switch regardless of the color type of the surface light source. A plurality of combinations of each groove to hold the lens unit and the image sheet are set,
An imaging position adjusting structure of a virtual switch characterized by the above. At least one of the lens unit or the image sheet is held by a holding body, and a protrusion that can engage with the groove is formed on the outer periphery of the holding body.
The imaging position adjusting structure for a virtual switch according to claim 1. The protrusion is disposed at a position shifted from a center line in a direction orthogonal to the optical axis direction of the lens unit or the image sheet.
The imaging position adjusting structure of the virtual switch according to claim 2. The grooves are arranged to face each other at a predetermined interval in the optical axis direction on the first and second opposing inner wall surfaces in the housing.
The imaging position adjusting structure for a virtual switch according to claim 1. The first and second opposed grooves are disposed opposite to each other at a predetermined interval in the optical axis direction on the first and second opposed inner wall surfaces in the housing, and the first and second opposed faces. On the third and fourth opposing inner wall surfaces different from the inner wall surface, they are opposed to each other with a predetermined interval in the optical axis direction, and the position in the optical axis direction is shifted by 1/2 pitch from the first and second grooves. And third and fourth grooves,
The imaging position adjusting structure for a virtual switch according to claim 1. The groove is a spiral groove formed in a spiral shape on the inner peripheral surface of the housing.
The imaging position adjusting structure for a virtual switch according to claim 1.

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