JP2000221574A - Image pickup module equipped with switching means - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make switchable an image pickup module between for visible light and invisible light and to miniaturize the module by making the thickness of filters for visible light and invisible light mutually different, making the flange back thereof virtually the same, and making the thickness of a part, in which the filter is fit, different from the thickness of other part on the side of the filter which is made thick. SOLUTION: In order to keep the thickness of the invisible light image pickup filter 101 as it is and make the thickness of the visible light image pickup filter 102 large, the thickness of the part of the filter 102 fit in a filter fitting part 103 is made the same as the thickness of the filter 101, and the thickness of other part is made large. Therefore, the thickness of the filter 102 is made large without making a distance between a lens 3 and an image pickup part 4 long and without making the filter 101 thin. Then, the flange back of the filter 101 can be made virtually coincident with that of the filter 102.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging module for switching between visible light and invisible light.

[0002]

2. Description of the Related Art <Conventional input means to computer> As an input device to a computer, a mouse is overwhelmingly used. However, what can be done with a mouse is to serve as a two-dimensional pointing device, such as moving a cursor and selecting a menu. Since the mouse can handle two-dimensional information, it is difficult to select an object having a depth such as an object in a three-dimensional space. Also,
When creating animations, it was difficult to make natural movements with the mouse to move the characters.

<Existing three-dimensional pointing device>
To compensate for the difficulty of pointing in 3D space, 3
Dimensional pointing devices have been developed.

[0004] However, there is a problem that the cursor and the viewpoint cannot be controlled as desired when actually operated. For example, when trying to turn left or right, the user pushes forward or backward, and the cursor moves in an unexpected direction or the viewpoint moves.

<Wearable three-dimensional input device> For such a three-dimensional pointing device, a device for inputting using a hand gesture or gesture has been developed. They are called data gloves, data suits, and cyber gloves. These are, for example, data gloves that are glove-like devices with optical fibers running over the surface.

[0006] The optical fiber passes through the finger joint,
Bending a finger changes the conduction of light. By measuring the light conduction, it is possible to determine how much the joint of each finger is bent. The position of the hand itself in the three-dimensional space is measured by a magnetic sensor on the back of the hand. If you decide the gesture and the corresponding instruction, such as moving up with the index finger, you can use the data glove to change the viewpoint in various ways in 3D space and just walk around (walkthrough )be able to.

<Problems of data glove> However, there are some problems. First, the price is expensive, and it is difficult to use it easily for home use. Since the angle of the finger joint is measured, it is assumed that, for example, only the index finger is extended, and the bent state of the other fingers is defined as a forward instruction. Even if you extend your finger to a bite, the angle of the second joint of the index finger is 18
Since it is rarely complete at 0 degrees, it is difficult to recognize that it is extended unless it is completely extended unless you make a play part.

Also, since the data glove is worn,
Natural operations are hindered. In addition, the light conduction state must be calibrated between the open state and the closed state of the hand each time it is mounted, so that it cannot be used easily. In addition, since the optical fiber is used, there is a problem that if the optical fiber is continuously used, the fiber is cut off and is close to a consumable.

[0009] In addition, even if the gloves are not exactly the same size as the expensive and time-consuming device, the gloves may shift during use and deviate from the calibrated values. It is difficult to recognize fine gestures. Due to various problems, data gloves are not as popular as expected at first despite the fact that they were devices that triggered VR (virtual reality, virtual reality) technology. Also, the price has not been reduced, and there are many problems in terms of usability.

<Problems of Recognition Technique of Gesture and Hand Gesture Using Image> On the other hand, several attempts have been made to input a hand and gesture without wearing a special device such as a data glove. I have. For example, research has been conducted to analyze a moving image such as a video image to recognize a hand shape. However, these methods have a problem that it is difficult to cut out only a hand in the case of recognizing a target image and a hand gesture from a background image.

For example, consider the case of cutting out using color. Since the color of the hand is flesh color, a method of cutting out only the flesh color part can be considered. However, if there are beige clothes or walls in the background, it is difficult to identify the skin color. Further, even if the adjustment is performed so that beige and flesh color can be distinguished, it is difficult to cut out regularly because the color tone changes if the illumination changes.

In order to avoid such a problem, a measure has been taken to limit the background image, such as placing a blue mat on the background, to facilitate clipping. Also,
Video image recognition processing such as clipping as described above,
The amount of calculation is very large. For this reason, the current state of the art is that the current personal computer cannot process images generated at 30 frames per second. Therefore, it is impossible to perform motion capture or the like by processing a video image in real time.

<Gesture Recognition Using Markers> Also, there are devices that attach color markers and light emitting parts to hands and parts of the body, detect them by images, and capture the shapes and movements of hands and bodies. Has been put to practical use. Used in production sites such as CG animation and TV games, the CG character is moved according to the input human motion.

However, considering that an individual-level user uses such a device, it is a great disadvantage that the user must wear the device every time the operation is performed, and the range of application is greatly restricted. Further, as seen in the example of the data glove, the durability of a device which is used by attaching the device to a movable part such as a hand tends to be a problem.

<Range Finder> There is a device called a range finder for inputting a distance image. As a typical principle, spot light or slit light is applied to a target object, and the target object is obtained from the light receiving position of the reflected light by the principle of triangulation. In order to obtain two-dimensional distance information, spot light or slit light is mechanically scanned.

Although this device can generate a very accurate range image, the configuration of the device is large and the cost is high. Also, it takes time to input, and it is difficult to perform processing in real time.

There is also a method in which two cameras are used to capture images from two directions, and three-dimensional information is generated from corresponding points in both images by using trigonometry. But,
Finding the corresponding points in the two images is difficult, especially in a complex background. Also, due to its difficulty, real-time processing requires a great deal of computer power.

<Cutout of Character from Image> Next, apart from the above-described input device, problems of the camera technology with respect to the prior art will be described. In the conventional camera technology, in order to combine a character with a background (chroma key), it was necessary to photograph the character in advance with a blue background and to easily cut out the character.

For this reason, there are restrictions on the shooting location such as a studio where shooting can be performed with a blue background. Alternatively, in order to cut out a character from a video shot in a non-blue-back state, the character cutout range has to be manually edited for each frame, which is extremely time-consuming.

Similarly, in order to generate a character in a three-dimensional space, a method is used in which a three-dimensional model is created in advance, and a picture of the character is pasted (texture mapping) there. . But,
The generation of the three-dimensional model and the texture mapping were troublesome, and could hardly be used for purposes other than those that could be expensive, such as movie production.

<Problem Proposal> As described above, conventionally, there has been no direct instruction type input device capable of easily inputting a gesture or movement without mounting a special device. In particular, there is no simple device that can easily perform pointing and change of viewpoint in a three-dimensional space. Also, natural movements cannot be given to animated characters or the like using the user's gestures and movements as they are.

Further, in the conventional camera, it is not possible to cut out only a specific character or to easily input depth information of the character. <Invention of imaging apparatus having light emitting means as a solution thereto>
In order to solve the above problems, a device capable of inputting the shape, movement, distance information, and the like of an object without contact has been invented. The input device emits light, and captures light reflected by the target object as an image. When the surface of the object is a substantially uniform diffuse reflection surface, the intensity of the reflected light has a close relationship with the distance to the object.

The reflected light from the place where the object is present has a certain value, and there is almost no reflected light from a distant background.
The shape of the object can be extracted. In addition, by processing the shape, the center of gravity position and size, horizontal direction,
It is possible to extract various features such as movement and deformation of the shape in the vertical direction and the time series of the shape. Further, since the unevenness of the object can be regarded as a difference in the amount of reflected light, a three-dimensional structure of the target object can be obtained.

<Reduction of the influence of external light> Even if light is emitted and the reflected light is simply received, external light such as illumination or sunlight enters into the light, and a correct amount of received light can be obtained. Absent. In order to input an image of reflected light, the light emitting unit and the light receiving unit are operated by a control signal of a timing generating unit that generates a certain timing. The reflected light image can be obtained by taking the difference between the received light image when the light emitting unit is not emitting light from the received light image when the light emitting unit is not emitting light.

Specifically, for example, a reflected light image can be obtained by operating an image sensor having two capacitors in a cell corresponding to one pixel in synchronization with a light emitting unit. The charge received and generated by the photoelectric conversion unit of the cell is selected so that either one of the two capacitors can be stored. Then, the charge received and generated when the light emitting unit is emitting light is stored in the first capacitor, and the charge received and generated when the light emitting unit is not emitting light is stored in the second capacitor. If a mechanism for outputting the difference between the two charge amounts when reading out the charge from the cell is prepared, the difference between the two capacitors, that is, image data of only the reflected light can be obtained.

[0026]

A normal image pickup device can pick up not only invisible light but also visible light. For this reason, when imaging the reflected light of the invisible light, it is necessary to block the visible light. Therefore, for example, a filter that passes only the region of the invisible light must be provided between the lens and the image sensor.

On the other hand, if the invisible light is blocked and only the visible light is imaged, normal imaging can be performed. Again, for example,
A filter that allows only visible light to pass must be provided between the lens and the image sensor.

By switching between these two filters,
Both visible light and invisible light can be imaged. However, the flange back (distance from the end of the lens barrel to the image plane) of the lens differs between visible light and invisible light. For example, when light having a longer wavelength than visible light, such as near-infrared light, is used as the invisible light, the invisible light flange back is generally longer than the visible light flange back. However, changing the distance between the lens and the image sensor during invisible light photographing and visible light photographing by mechanical movement or the like has a problem that the cost is high and the device is easily broken. One way to virtually lengthen the flange back is to increase the thickness of the filter inserted between them.

However, when the thickness of the filter for visible light is simply increased, the filter fitting portion to be fitted for switching to the filter for invisible light becomes thick, and there is a problem that the filter comes into contact with the lens or the surface of the image pickup device. Conversely, when the thickness of the filter for invisible light is reduced, there has been a problem that the filter is thin and easily broken.

When a user considers controlling the machine by putting his / her hand in front of the imaging device and moving it, the place where the hand is easy to reach depends on the physique and posture of the user. When the orientation of the imaging module is fixed, the user has to adjust the position of his / her hand according to the imaging range, which hinders natural operation and promotes fatigue. Problem.

In order to solve such a problem, measures are taken to make the photographing module movable, for example, by rotating it. However, when the angle is changed or the like is moved, the display unit for displaying the status such as whether the module is turned on may be invisible.

Further, invisible light is actually contained in a large amount in indoor lights such as fluorescent lights. If the invisible light is simply imaged, there is a problem that the invisible light from the room light becomes noise and the image cannot be accurately captured.

In order to solve this problem, it is necessary to remove invisible light from a fluorescent lamp. Actually, the blinking of the fluorescent lamp is not completely 50 Hz (60 Hz in Kansai), so in order to eliminate this blinking, the blinking period of the fluorescent lamp must be detected. However, there are individual differences in the flicker of the fluorescent lamp. For this reason, if the detecting unit for detecting the cycle of the fluorescent lamp is not in the same direction as the image sensor, a problem arises in that a fluorescent lamp different from that which affects the image sensor is detected and noise cannot be removed. Was.

[0034]

In order to solve these problems, the present invention provides a first filter for imaging invisible light, and a visible light having a thickness different from that of the first filter. Filter, a switch for switching between these two filters, and a first filter and a second filter which are movable in conjunction with the switch to switch between the first filter and the second filter. A switching means comprising a filter fitting section in which a filter is disposed; a lens for condensing invisible light or visible light; and a first filter condensed by the lens and switched by the switching means. An imaging element for imaging the invisible light that has passed through or the visible light that has passed through the second filter.

Also, an area image sensor for obtaining a difference between charges received by the light receiving cells arranged in an array, a timing signal generating means for generating a pulse signal or a modulation signal, and a light receiving cell of the area image sensor for receiving light. A control signal for individually controlling, a control signal generating unit that generates based on a signal from the timing signal generating unit, and a light emitting unit that emits light whose intensity changes based on a signal from the timing signal generating unit, A first filter for imaging reflected light of light emitted by the light emitting means, a second filter for imaging visible light having a thickness different from that of the first filter, and switching between these two filters A first filter so as to be movable in conjunction with the switch and to switch between the first filter and the second filter; A switching means comprising a filter fitting portion in which a second filter and a second filter are arranged; a lens for condensing invisible light or visible light; and a second lens condensed by the lens and switched by the switching means. An imaging element for imaging invisible light passing through the first filter or visible light passing through the second filter.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS <Description of Basic Principle> First, the basic principle and basic configuration of an imaging apparatus to which the present invention is applied will be described. This imaging apparatus has means for emitting invisible light, and images reflected light from the object. By operating the light emitting unit and the imaging unit synchronously, the light emitting unit and the image pickup unit are separated from external light such as indoor lighting and sunlight, and only the light reflected by the light emitting unit is captured. The reflected light image is taken into a device such as a computer as input information, or the image is processed into various forms or information is extracted from the image and used as information for operating the device.

FIG. 1 shows the basic configuration of the present imaging apparatus. The light emitted from the light emitting unit 1 is reflected by the target object 2 and forms an image on the light receiving surface of the reflected light image detecting unit 4 by the light receiving optical system (lens) 3. The reflected light image detector 4 detects the intensity distribution of the reflected light, that is, the reflected light image. A mechanism for extracting only reflected light by separating it from external light in the reflected light image detection unit 4 will be described later.

The reflected light image detector 4 sequentially outputs the amount of reflected light from each pixel of the reflected light image. The output from the reflected light image detection unit is amplified by the amplifier 5, converted into digital data by the A / D converter 6, and stored in the memory 7. This memory 7 at the right time
The stored data is read. The read data is processed in, for example, a characteristic information generation unit (not shown). The whole control is performed by the control unit 9 at an appropriate timing.

In the reflected light image detecting section 4, cells which are unit light receiving sections corresponding to one pixel of an image are two-dimensionally arranged. In this respect, it is similar to other imaging devices such as a CCD image sensor. The difference is that the cell structure has a mechanism for extracting only reflected light by separating it from external light. The cell includes a photoelectric conversion unit, a storage direction control unit, first and second charge storage units, and a selection output unit.

The photoelectric conversion unit converts incident light into electric charges. The first and second charge storage units are means for storing charges generated in the photoelectric conversion unit. The storage direction control unit is a unit that controls which of the first and second charge storage units stores the charge generated in the photoelectric conversion unit. The selection output section is a means for selecting one of the first and second charge storage sections and reading out the charge outside the cell.

The following operation is performed to obtain one reflected light image. First, the light emitting unit 1 emits a pulse. While emitting light, the charge generated in the photoelectric conversion unit is stored in the first charge storage unit. Next, while no light is emitted, the charge generated in the photoelectric conversion unit is stored in the second charge storage unit.

As described above, in the first charge storage portion, the amount of charge received by reflected light, room illumination, and external light such as sunlight is:
The second charge accumulating portion accumulates the amount of electric charge that has received only external light. When reading charges from the cell, the two charge storage amounts are read in order and the difference is taken out by an external difference circuit. When the accumulation amount of the second charge accumulation unit is subtracted from the accumulation amount of the first charge accumulation unit, only the reflected light component is extracted.

In the above description, the charge is stored once in the first and second charge storage units, but the number is not limited to this. For example, accumulation in two charge accumulation units may be repeated ten times. Further, the number of times of charge storage in the first and second charge storage units may be different. For example, 1 ms may be stored in the first charge storage unit, then 2 ms may be stored in the second charge storage unit, and finally 1 ms may be stored again in the first charge storage unit. In this case, it is hard to be affected by the fluctuation of the external light.

The light emitting section 1 emits invisible light which is invisible to human eyes. More specifically, an LED that emits near-infrared light
Is preferable because of its cost and ease of incorporation into the device. Since it is invisible light, the user does not need to feel glare.

More preferably, a light receiving optical system (lens)
Is provided with a wavelength-selective optical filter (not shown). When near-infrared light is used, this filter passes near-infrared light, which is an emission wavelength, and blocks visible light and far-infrared light. Therefore, much of the external light that becomes noise is cut off.

The configuration of the imaging device described above is only one example. In practice, devices for obtaining reflected light images in various forms can be configured. In this patent, since the invention mainly focusing on the positional relationship between the light emitting unit and the light receiving optical system (lens) is described, the detailed configuration of the imaging element itself does not matter.

In the above description, an image pickup device having two charge storage units in a unit cell has been described as an example. However, for example, there is only one charge storage unit in a cell, and a mechanism for obtaining a difference is described below. May be prepared. With the same concept, this imaging device can be configured using an existing CCD image sensor or the like.

<Utilization of Reflected Light Image> The reflected light from the object decreases significantly as the distance to the object increases. When the surface of the object scatters light uniformly, the amount of light received per pixel of the reflected light image decreases in inverse proportion to the square of the distance to the object. Therefore, when an object is placed in front of the input device, the reflected light from the background becomes almost negligible, and a reflected light image from only the object can be obtained.

For example, when a hand is brought in front of the input device, a reflected light image from the hand is obtained. At this time, each pixel value of the reflected light image represents the amount of reflected light received by the unit light receiving cell corresponding to that pixel.

The amount of reflected light is affected by the properties of the object (specular reflection, scattering, absorption, etc.) of the object, the direction of the object surface, the distance of the object, and the like. In the case of a scattering object, the amount of reflected light has a close relationship with the distance to the object. Since a hand or the like has such a property, the reflected light image when the hand is put out reflects the distance of the hand, the inclination of the hand (partially different distance), and the like. Therefore, by extracting these pieces of characteristic information, it is possible to input and generate various information.

Representative examples of how to process the reflected light image are extraction of distance information and extraction of an area. As mentioned earlier,
If the object has a uniform and uniform scattering surface, the reflected light image can be regarded as a distance image. Therefore, the three-dimensional shape of the object can be extracted. If the object is a hand,
The inclination of the palm can be detected. The tilt of the palm appears as a partial difference in distance.

If the pixel value changes when the hand is moved, it can be regarded that the distance has moved. Also, since there is almost no reflected light from a distant object such as the background, the shape of the object can be easily cut out by processing to cut out an area above a certain threshold from the reflected light image.

For example, if the object is a hand, it is very easy to cut out a silhouette image thereof. Further, since the pixel value is closely related to the distance, it is possible to obtain information on the unevenness of the object. This indicates that a three-dimensional shape can be obtained.

Various characteristic information can be extracted from the reflected light image. There are various methods for extracting the characteristic information or the characteristic information. For example, you can extract the shape area and the position of the center of gravity, the horizontal and vertical directions, and their temporal changes. In addition, the position of the fingertip can be detected from the shape of the hand. It is also possible to obtain a feature amount that also uses distance information.

Information such as gestures and pointing is generated from these pieces of characteristic information, so that a computer or the like can be operated. It is also possible to extract and use the three-dimensional information of the target object. Further, the present invention can be applied not only to computers but also to various products such as devices such as AV devices and home electric appliances, medical devices that need to be operated in a non-contact manner, and devices such as factories that want to operate with dirty hands.

<Explanation of Converting Brightness into Distance> As described above, in this apparatus, light is emitted by the light emitting unit, and the reflected light of the object by the light is acquired as an image. Therefore, the reflected light increases when the object is near, and decreases when the object is far away.
Assuming that the object surface is perpendicular to the optical axis and that the surface is a perfect diffusion surface, the amount of light received by the light receiving cell (corresponding to one pixel of the reflected light image) that receives the reflected light from the object surface Is inversely proportional to the square of the distance to the object plane.

In practice, the object surface may not be a perfect diffusion surface, and the amount of reflected light attenuates unless the object surface is perpendicular to the optical axis. If the light emitting unit does not uniformly illuminate the target space, the amount of reflected light varies depending on the position of the target object. Therefore, it is necessary to perform various corrections in order to obtain the accuracy. However, basically, the amount of reflected light, that is, the pixel value has a relationship with the distance.

The object can be cut out from the background by using the reflected light as described above. On the other hand, instead of reflected light,
Normal image (passive with visible light) imaging is also possible. The present invention enables both normal imaging and imaging of a distance image by reflected light.

FIG. 2 shows a front view and a side view of the present invention. FIG. 3 is a view of the present invention from almost right above. The housing is sealed so that light from the surroundings does not leak. A radiation plate or the like for dissipating heat is installed in a portion that generates heat, such as a power supply. A plurality of LEDs 1 serving as light emitting units are arranged around the lens 3. A reflected light image detection unit 4 is disposed behind the lens 3.

Below the LED 1, a power ON / OFF indicator 31 for indicating whether the power is on or not is provided.
For example, when the power is on, the light turns green, and when the power is off, the light turns off.
/ OFF can be confirmed. Power ON / O
The switch of the FF can be attached to the rear of the housing. Alternatively, it is also possible to turn on / off by software from a computer such as a connected personal computer.

In order to remove noise due to external light such as a fluorescent lamp, it is necessary to detect the frequency of the external light.
The external light detection unit 32 for this purpose is installed on the same side as the lens, in this example, on the upper side opposite to the power ON / OFF indicator 31.

This housing is supported by a U-shaped support portion, and the contact portion is, as can be seen from the side view in FIG. A groove is dug so that the housing fits exactly in the hole where it is located, so that it can be supported and rotated.

FIG. 3 shows a switch section of the switching section 10 for switching between invisible light and visible light imaging. FIG. 4 shows details of the switching unit 10.
The switching unit 10 has two filters fitted therein, is movable by a changeover switch, and is capable of switching the two filters for the lens. The filter fitting unit 103, the invisible light imaging filter 101, and the visible light imaging filter 1
02.

The invisible light imaging filter 101 is, for example,
It is composed of a near-infrared pass bandpass filter (BPF), which passes only near-infrared light emitted by the LED 1 of the light emitting unit and blocks light of other wavelengths.

One visible light imaging filter 102 is formed of an acrylic plate. In the case of turning on the LED 1 of the light emitting unit even during visible light imaging, it is necessary to use a visible light passing bandpass filter in order to block near-infrared light. If the sensitivity characteristic of the image sensor is significantly different from the luminosity, a luminosity correction filter can be used.

Here, if the thicknesses of the visible light and invisible light filters are the same, as shown in FIG. 6, the position of the image plane differs between invisible light imaging and visible light imaging. The flange back 104 (the distance from the end of the lens barrel to the imaging plane, abbreviated as FB) 104 when using the invisible light imaging filter is shorter than the flange back 105 when using the visible light imaging filter. When the thickness of the filter is the same, the position of the imaging surface needs to be physically different as shown in FIG.
However, physically moving the position of the imaging unit 4 is not desirable because it requires a large-scale mechanism and reduces accuracy.

Therefore, as shown in FIG. 5, by making the thickness of the filter different, the difference in the flange back length is absorbed. For example, when a filter for invisible light imaging is used, the flange back is Fi, the refractive index of the filter is ni, the thickness of the filter is Wi, the flange back is Fd for visible light imaging, the refractive index of the filter is nd, and the filter is nd. The thickness of Wd
Then, Fd + (1 + 1 / nd) · Wd = Fi + (1 + 1 / n)
i) · Wi holds. Therefore, the thicknesses Wi and Wd of the filter may be determined so as to satisfy this relationship.

The invisible light imaging filter 10
Flange back 1 for invisible light imaging by reducing the thickness of 1
There is also a method of virtually matching the flange back 105 at the time of imaging with visible light. Invisible light imaging filter 101
In the method of increasing the thickness of the visible light imaging filter 102 while keeping the thickness of the filter unchanged, the distance between the lens 3 and the imaging unit 4 is increased, and it is difficult to reduce the size of the apparatus. In order to reduce the size of the device, the thickness of the invisible light imaging filter 101 is reduced because the distance between the lens 3 and the imaging unit 4 is not desired to be large, and the filter is damaged during the manufacturing process, thereby greatly reducing the yield. It is a factor to make it. Further, depending on the type of the filter, the performance deteriorates when the filter is made thin.

To solve such a problem, FIG.
As shown in the figure, in order to increase the thickness of the visible light imaging filter 102 while keeping the thickness of the invisible light imaging filter 101, the thickness of the portion fitted into the filter fitting portion 103 is set to the invisible light The thickness is the same as the thickness of the imaging filter 101, and the other portions are thickened. For this reason, the thickness of the visible light imaging filter 102 can be increased without increasing the distance between the lens 3 and the imaging unit 4 and without reducing the thickness of the invisible light imaging filter 101. The invisible light imaging filter flange back 104 and the visible light imaging filter flange back 105 can be virtually matched.

FIG. 7 shows an image obtained by imaging as described above.
Shown in FIG. 7A shows an image of visible light imaging, and FIG.
Is an image captured by invisible light. In the visible light imaging, a normal image is obtained, whereas in FIG. 7B, it can be seen that an image in which only the hand is cut out from the background can be captured.

Further, in the product process, it is necessary to focus the lens. In order to perform focusing of invisible light, it is necessary to cause the LED 1 to emit light in the conventional method. However, according to the present invention, if focusing is performed with visible light, invisible light can be imaged with the same focus. For this reason, the inspection jig can be performed in a configuration excluding the LED 1 and the invisible light imaging filter 101.

[0072]

As described above, according to the present invention, different filter thicknesses can be realized without increasing the size of the imaging module and without causing damage to the filter, and virtually eliminate the flange back from visible light and invisible light. Switching between visible light and invisible light can be realized using the same light.

[Brief description of the drawings]

FIG. 1 is a configuration of an input device having a light emitting unit and an imaging unit to which the present invention is applied.

FIG. 2 is a front view and a side view showing an overview of the present invention.

FIG. 3 is a diagram showing an overview of the present invention as viewed from directly above.

FIG. 4 is a front view of a switching section for switching between visible light and invisible light.

FIG. 5 is a view showing a difference in thickness between visible light and invisible light filters.

FIG. 6 is a diagram showing the difference in the length of the flange back between visible light and invisible light.

FIG. 7 is a diagram showing imaging results with visible light and invisible light.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Light emission part 2 ... Target object 3 ... Light receiving optical system (lens) 4 ... Reflected light image detection part 5 ... Amplifier 6 ... A / D converter 7 ... Memory 8 ... I / F circuit 9 ... Control part 10 ... Switching part 101: Filter for invisible light imaging 102: Filter for visible light imaging 103: Filter fitting part

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor: Takahiro Murata 1st, Komukai Toshiba-cho, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Inside the Toshiba R & D Center (72) Inventor: Minoru Ishikawa Komukai, Saiyuki-ku, Kawasaki City, Kanagawa Prefecture No. 1, Toshiba-cho, Toshiba R & D Center (72) Inventor Akira Morishita, No. 1, Komukai Toshiba-cho, Koyuki-ku, Kawasaki-shi, Kanagawa, Japan Toshiba R & D Center

Claims (5)

[Claims] 1. A first filter for imaging invisible light, a second filter for imaging visible light having a thickness different from that of the first filter, and a switch for switching between these two filters. A switching means comprising a filter fitting portion in which the first filter and the second filter are arranged so as to be movable in conjunction with the switch and to switch between the first filter and the second filter; A lens for condensing invisible light or visible light, and an image of invisible light condensed by the lens and passing through the first filter switched by the switching means or visible light passing through the second filter. An imaging module, comprising: an imaging element. 2. An area image sensor for taking a difference between charges received by light receiving cells arranged in an array, a timing signal generating means for generating a pulse signal or a modulation signal, and a light receiving cell of the area image sensor for receiving light. A control signal for individually controlling, a control signal generating unit that generates based on a signal from the timing signal generating unit, and a light emitting unit that emits light whose intensity changes based on a signal from the timing signal generating unit, A first filter for imaging reflected light of light emitted by the light emitting means, a second filter for imaging visible light having a thickness different from that of the first filter, and switching between these two filters A switch, and a first filter that is movable in conjunction with the switch to switch between the first filter and the second filter. A switching means comprising a filter fitting part in which a second filter is disposed; a lens for condensing invisible light or visible light; and a first light condensed by the lens and switched by the switching means. An image pickup device for picking up an image of invisible light passed through the filter or visible light passed through the second filter. 3. A method for absorbing a difference between a distance from a lens barrel end of the lens to an image forming surface in a visible light region and a distance from the lens barrel end of the lens to an image forming surface in an invisible light region. 3. The imaging module according to claim 1, wherein the thickness of the filter is different from that of the second filter. 4. The filter according to claim 1, wherein at least one of the first filter and the second filter has a thickness different from that of a portion fitted to the filter fitting portion and a thickness of the other portion. The imaging module according to claim 1 or 2, wherein 5. The imaging apparatus according to claim 2, wherein when imaging visible light using the second filter, a signal generated by the timing signal generation unit is controlled so that the light emission unit does not emit light. module.