JP6739369B2 - How to adjust the camera focus in the intercom device with camera - Google Patents

Description

The present invention relates to a camera focus adjustment method in an intercom device with a camera such as an intercom slave.

Conventionally, an intercom slave, which is an example of an intercom device, may be provided with a camera for capturing an image of a visitor or the like. As such an intercom slave unit with a camera, for example, there is one disclosed in Patent Document 1, and a lens barrel for holding a lens and a lens holder are screwed together to form a lens unit. Was installed in the body case. Further, after the lens unit is installed, the focus is adjusted by adjusting the screwing degree of the lens barrel with respect to the lens holder, and the focus position of the lens is adjusted to the desired focus position.

JP, 2010-93648, A

Conventionally, since the focus adjustment depends on the experience of the operator, there is a problem that the adjustment work takes time, and a difference inevitably occurs for each operator, so that the quality tends to vary from product to product.

Therefore, the present invention has been made in view of the above problems, and it is possible to shorten the time for adjusting the focus of the camera and adjust the focus of the camera in the interphone device with a camera in which the quality is less likely to vary from product to product. It is intended to provide a method.

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention provides a lens, a cylindrical lens barrel for holding the lens, and a lens for supporting the lens barrel by screwing with a rear portion of the lens barrel. A lens barrel rotator that rotates a lens barrel, and an affixing device that affixes the lens barrel and the lens holder to an intercom device that includes a camera that includes a holder and a circuit board that is arranged on the rear side of the lens holder. The lens barrel is rotated by an adjusting device that controls the operation of the lens barrel rotator and the fixing device and also makes a determination regarding the adjustment of the focus of the camera, and the degree of screwing of the lens barrel into the lens holder is adjusted. A method of adjusting the focus of a camera in an intercom device with a camera for adjusting the focus of a camera by performing a first step of capturing an image for predetermined adjustment by the camera and capturing the image data thereof; While rotating in a predetermined direction, the evaluation value is calculated from time to time by a predetermined evaluation function based on the contrast value in a predetermined area of the captured image data, and the evaluation value is compared with a preset threshold value. While the value is below the threshold, the second step of continuing the rotation of the lens barrel in the predetermined direction and calculating the evaluation value and stopping the rotation of the lens barrel when the evaluation value becomes equal to or higher than the threshold value It is characterized in that the third step of determining that the lens is in focus and the fourth step of fixing the lens barrel and the lens holder to each other are performed by determining that the lens is in focus.
Further, in the invention described in claim 2, in the invention described in claim 1, before the first step, a predetermined image for adjustment is imaged by a camera, the image data thereof is taken in, and the lens barrel is predetermined. While rotating in the direction, the evaluation value is calculated from time to time by a predetermined evaluation function based on the contrast value in the predetermined area of the captured image data, and while the evaluation value is increasing, the lens barrel is rotated in the predetermined direction. Further, the calculation of the evaluation value is continued, and when the evaluation value starts to decrease, the pre-process of setting the evaluation value immediately before the decrease as the threshold value is executed.
According to the first and second aspects of the present invention, since it is not necessary for the operator to adjust the focus of the camera based on the experience of the operator, the time required for the adjustment work can be shortened, and the focus accuracy is constant. It will be possible to easily supply the product.

According to a third aspect of the present invention, in the first or second aspect of the present invention, a notch portion that exposes a threaded portion of the lens barrel is provided at a threaded portion of the lens holder that is threaded with the lens barrel. The adjusting device is provided with an adhesive ejector for ejecting an adhesive as a fixing device, and in the fourth step, the adhesive is ejected toward the cutout portion.
According to the third aspect of the present invention, the cutout portion can be used as a target for discharging the adhesive, and the fixation of the lens barrel and the lens holder by the adhesive is stable. There is also an advantage that it is easy to visually confirm the degree of fixation of.

According to the present invention, since it is not necessary for the operator to adjust the focus of the camera based on the experience of the operator, it is possible to shorten the time required for the adjustment work and easily supply a product of a certain quality with respect to the focus accuracy. It becomes possible.

It is a block configuration diagram of an adjusting device for adjusting the focus of a camera provided in the intercom slave. It is explanatory drawing which showed the intercom subunit|mobile_unit from the front side. It is explanatory drawing which showed the vertical cross section of the intercom subunit. It is explanatory drawing which showed the lens holder, (a) is a front view, (b) is a right side view, (c) is a perspective explanatory view. It is explanatory drawing which showed the lens barrel, (a) is a perspective explanatory view, (b) is a side view. It is explanatory drawing which showed the 3-line chart used as a figure for adjustment. It is explanatory drawing which showed the characteristic of a contrast value and an evaluation function. It is a flowchart figure regarding adjustment of the focus of a camera. It is a flowchart figure regarding adjustment of the focus of a camera. It is a flowchart figure regarding adjustment of the focus of a camera.

Hereinafter, a method and an apparatus for adjusting a focus of a camera in an intercom slave having a camera according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block configuration diagram of an adjusting device 31 for adjusting the focus of a camera provided in the intercom slave 1. FIG. 2 is an explanatory view showing the intercom slave 1 from the front side, and FIG. 3 is an explanatory view showing a vertical cross section of the intercom slave 1. 4A and 4B are explanatory views showing the lens holder 12, where FIG. 4A is a front view, FIG. 4B is a right side view, and FIG. 4C is a perspective explanatory view. 5A and 5B are explanatory views showing the lens barrel 11, where FIG. 5A is a perspective explanatory view and FIG. 5B is a side view.

First, the intercom slave unit 1 will be described. The intercom slave unit 1 has a main body case including a front case 2 arranged on the front side and a rear case 3 arranged on the rear side. A camera window 4 is opened at the upper part of the front surface of the case, and the camera is installed in the main body case so that the lens 5 is exposed in the camera window 4. Further, on the right side of the camera window 4, a microphone unit 7 for calling is provided. Further, a call button 8 operated when a visitor calls a resident and a speaker unit 9 for a call are provided on the lower front portion of the main body case. The intercom slave unit 1 is installed on the wall surface of the entrance of the dwelling unit, and when the call button 8 is operated by the visitor, the intercom master unit (not shown) installed in the dwelling unit. And activate the camera to image the visitor. The video imaged by the camera is displayed on the monitor provided in the intercom master unit. The lens cover 10 is attached to the main body case so as to cover the front of the camera.

The camera includes a lens 5, a lens barrel 11 that holds the lens 5, a lens holder 12 that supports the lens barrel 11, and a circuit board 13 on which an image pickup device (not shown) and the like are mounted. The lens holder 12 is provided with a cylindrical portion 22 projecting forward at a predetermined position of a base portion 21 serving as a base. A female screw portion (not shown in FIG. 4) is provided on the inner surface of the cylindrical portion 22 so that the cylindrical portion 22 functions as a supporting portion that supports the lens barrel 11. Further, a pair of notches 23, 23 are provided at the tip of the cylindrical portion 22, and when the lens barrel 11 is supported, the male screw portion 15 of the lens barrel 11 to be described later of the lens barrel 11 is provided inside the notches 23, 23. Part of it is exposed. On the other hand, the lens barrel 11 is formed in a cylindrical shape that extends in the front-rear direction and opens in the front-rear direction, and accommodates the lens 5 inside and can hold the lens 5 with a part of the lens 5 exposed from the front surface. There is. A male screw portion 15 that can be screwed into a female screw portion of the lens holder 12 is provided on the rear peripheral surface of the lens barrel 11. In addition, 24 is a screwing portion for integrating the lens holder 12 and the circuit board 13.

Then, when assembling the camera configured as described above, after holding the lens 5 in the lens barrel 11, the male screw portion 15 of the lens barrel 11 is screwed into the female screw portion of the lens holder 12, and the lens barrel 11 and the lens holder 12 are screwed. Integrate with. Then, the lens holder 12 and the circuit board 13 may be integrated by screwing or the like. Further, after the camera is assembled, in order to adjust the focal position of the lens 5 to a desired focus position, the screwing degree of the lens barrel 11 with respect to the lens holder 12 is adjusted.

Here, an adjusting method for adjusting the focus of the camera in the intercom slave 1 and the adjusting device 31, which are the main parts of the present invention, will be described.
The adjusting device 31 includes an image input unit 32 to which image data captured by a camera is input, a lens barrel rotator 33 for adjusting the screwing degree of the lens barrel 11 with respect to the lens holder 12, and a mirror with a predetermined screwing degree. An adhesive ejector 34 for fixing the barrel 11 and the lens holder 12 to each other, a drive unit 35 for operating the lens barrel rotator 33 and the adhesive ejector 34, and a focus based on the input image data. The control unit 36 is provided for determining the adjustment degree and controlling the operation of the drive unit 35. The lens barrel rotator 33 has, for example, a distal end formed like a wrench, and is provided with a gripping portion capable of gripping the vicinity of the distal end portion of the lens barrel 11, and a rotation drive portion for rotating the gripping portion while gripping the lens barrel 11. I have it. In addition, the adhesive ejector 34 is installed in a posture in which the ejection port for ejecting the adhesive is directed to the notch 23 of the lens holder 12 (that is, the notch 23 is a target for ejecting the adhesive). Since FIG. 1 is a block configuration diagram, only one is shown, but in reality, two units are provided according to the number of the notches 23.

Then, the adjusting device 31 adjusts the focus of the camera according to the flowcharts shown in FIGS.
That is, first, a figure for focus adjustment is arranged at a predetermined position on the front side of the camera, and image data obtained by capturing the figure with the camera is fetched from the image input unit 32 (S1). As a diagram for this focus adjustment, for example, a so-called three-line chart as shown in FIG. 6 may be used. Also, from the contrast value Ca in the central area of the image data and the contrast value Cb in the peripheral area (for example, two areas such as the upper right corner and the lower left corner), evaluation is performed by the evaluation function Ctotal shown in the following formula (1). A value is calculated (S2). Regarding the contrast values Ca and Cb, the difference between the signal values of the pixels adjacent to each other in each region is obtained, and the average value of the plurality of upper places where the absolute value of the difference is large is taken as the contrast values Ca and Cb. Then, based on the evaluation value of the evaluation function Ctotal, it is determined whether or not the focus is achieved, that is, whether or not the focus is achieved (S3). If it is determined that the focus is achieved (YES in S3), the adhesive ejector 34 is determined. The adhesive is ejected from the lens barrel 11 and the lens barrel 11 and the lens holder 12 are fixed in a focused state (S4). On the other hand, when it is determined that the subject is out of focus (NO in S3), the lens barrel 11 is rotated (S5), and the evaluation value is obtained by the evaluation function Ctotal (S2).
Ctotal=Ca+α*Cb (1)
Note that α is a proportional coefficient.

Further, prior to the adjustment work, a pre-process for setting a threshold value used when determining whether or not focusing is performed based on the evaluation value is executed. In this pre-process, first, the lens barrel rotator 33 is driven to rotate the lens barrel 11 in a predetermined direction (here, the + direction in FIG. 7 and the direction in which the degree of screwing increases) ( S11), the evaluation value in the evaluation function Ctotal is calculated at any time. Then, initially, the evaluation value should increase as shown in FIG. 7, so it is determined whether the evaluation value is increasing (S12), and while it is increasing (YES in S12), the evaluation function is increased. The maximum value of Ctotal is updated (S13). However, as shown in FIG. 7, when the evaluation value exceeds the peak, the evaluation value starts to decrease. Therefore, at the timing when the value of the evaluation function Ctotal starts to decrease (NO in S12), the driving of the lens barrel rotator 33 is stopped and the mirror is stopped. The rotation of the cylinder 11 is stopped (S14), and the evaluation value immediately before the decrease is stored as a threshold value (S15).

Regarding the adjustment work, the lens barrel rotator 33 is driven to rotate the lens barrel 11 in a predetermined direction (S21), and the evaluation value of the evaluation function Ctotal is calculated at any time. Further, it is determined whether or not the evaluation value is equal to or more than the threshold value set as described above (S22), and while the evaluation value is below the threshold value (NO in S22), the lens barrel 11 is moved in the predetermined direction. Continue to rotate. Then, when the evaluation value becomes equal to or more than the threshold value (YES in S22), the driving of the lens barrel rotator 33 is stopped to stop the rotation of the lens barrel 11 (S23), and it is determined that the focus is achieved in this state ( S24). If the evaluation value does not reach the threshold value even after the lapse of a predetermined time, it may be processed as a defective product.

According to the method of adjusting the focus of the camera in the intercom slave 1, the adjustment device 31 including the lens barrel rotator 33 and the adhesive ejector 34 captures a predetermined image for adjustment by the camera. In the first step of capturing image data, while rotating the lens barrel 11 in a predetermined direction, an evaluation value is calculated at any time by a predetermined evaluation function Ctotal based on a contrast value in a predetermined region of the acquired image data, and A second step of comparing the preset threshold value and continuing the rotation of the lens barrel 11 in the predetermined direction and the calculation of the evaluation value while the evaluation value is below the threshold value, and the evaluation value is equal to or higher than the threshold value. Then, the rotation of the lens barrel 11 is stopped and the third step of determining that the lens is in focus and the third step of fixing the lens barrel 11 and the lens holder 12 when it is determined that the lens is in focus 4 steps and are performed. Further, prior to such adjustment work, a predetermined adjustment drawing is taken by the camera, the image data thereof is taken in, and while the lens barrel 11 is rotated in a predetermined direction, a contrast value in a predetermined area of the taken-in image data is taken. The evaluation value is calculated from time to time by a predetermined evaluation function based on the above, and while the evaluation value is increasing, the rotation of the lens barrel 11 in the predetermined direction and the calculation of the evaluation value are continued, and the evaluation value starts decreasing. Therefore, the pre-process of setting the evaluation value immediately before the decrease as the threshold value is executed. Therefore, since it is not necessary for the operator to adjust the focus of the camera based on the experience of the operator, it is possible to shorten the time required for the adjustment work, and it is possible to easily supply a product of constant quality with respect to the focus accuracy. Become.

A pair of notches 23, 23 are provided at the tip of a cylindrical portion 22 provided in the lens holder 12 for supporting the lens barrel 11, and the notch 23 is provided when the lens barrel 11 is supported. A part of the male screw portion 15 of the lens barrel 11 is exposed inside the lens barrel 23, 23, and the adhesive dispenser 34 is positioned such that the discharge port through which the adhesive is discharged is directed to the notch 23 of the lens holder 12. The target is to discharge the adhesive through the notch 23. Therefore, there is a merit that the fixation of the lens barrel 11 and the lens holder 12 by the adhesive is stable, and it is easy to visually confirm the fixation condition of the lens barrel 11 and the lens holder 12, for example.

The method of adjusting the focus of the camera in the interphone device with a camera according to the present invention is not limited to the mode of the above-described embodiment. For example, not only the overall configuration of the intercom device but also the control related to the focus adjustment. The above can be appropriately changed as necessary without departing from the spirit of the present invention.

For example, in the above-described embodiment, the pair of cutouts 23, 23 are provided at the tip of the cylindrical portion 22 of the lens holder 12, but the number of the cutouts 23 can be changed as appropriate, and not the tip but the center. You may provide a slit-shaped notch in the part.
As the adhesive, for example, a UV curable adhesive may be used, and a UV irradiator may be separately provided in addition to the adhesive ejector. Alternatively, a thermosetting adhesive may be used and a heat irradiator may be separately provided. Furthermore, there is no problem even if an anaerobic adhesive is used.

Furthermore, when the lens barrel 11 and the lens holder 12 are fixed to each other, an adhesive is used in the above embodiment (that is, the fixing device is an adhesive ejector), but the lens barrel 11 and the lens holder 12 are combined. If it is made of resin, the lens barrel 11 and the lens holder 12 can be fixed to each other by crimping a heat-welding jig that serves as a fixing device to the screwed portion.
Furthermore, although the intercom slave is described in the above embodiment, if the interphone device has a camera, the focus of the camera can be appropriately adjusted by the adjusting method according to the present invention even in other intercom devices. it can.
In addition, what kind of adjustment diagram is used, whether the evaluation function is obtained based on the contrast value of which part of the adjustment diagram, or whether the evaluation function is obtained based on the contrast value of some place, Needless to say, what kind of coefficient is used as the proportional coefficient in the evaluation function can be appropriately changed.

1... Intercom handset, 11... Lens barrel, 12... Lens holder, 22... Cylindrical part, 23... Notch, 31... Adjusting device, 32... Image input part, 33... Lens barrel rotation Container, 34... Adhesive dispenser, 35.. Drive unit, 36.. Control unit.

Claims (3)

A lens, a cylindrical lens barrel that holds the lens, a lens holder that is screwed with a rear portion of the lens barrel to support the lens barrel, and a circuit board that is disposed on the rear side of the lens holder. A lens barrel rotator that rotates the lens barrel, a fixing device that fixes the lens barrel to the lens holder, and an operation of the lens barrel rotator and the fixing device for an intercom device having a camera. The focus of the camera is adjusted by rotating the lens barrel and adjusting the degree of screwing of the lens barrel to the lens holder, by an adjusting device having a controller that determines the focus adjustment of the camera. A method for adjusting the focus of a camera in an intercom device with a camera for adjusting,
A first step of capturing a predetermined image for adjustment by the camera and capturing the image data;
While rotating the lens barrel in a predetermined direction, an evaluation value is calculated at any time by a predetermined evaluation function based on a contrast value in a predetermined area of the captured image data, and the evaluation value and a preset threshold value are set. In comparison, while the evaluation value is below the threshold value, a second step of continuing the rotation of the lens barrel in a predetermined direction and calculating the evaluation value,
A third step of stopping the rotation of the lens barrel and determining that the lens is in focus when the evaluation value is equal to or more than the threshold value,
A method of adjusting a focus of a camera in an intercom device with a camera, which comprises performing a fourth step of fixing the lens barrel and the lens holder by determining that the lens is in focus. Prior to the first step, a predetermined adjustment drawing is taken by the camera, the image data thereof is taken in, and while the lens barrel is rotated in a predetermined direction, a contrast value in a predetermined area of the taken-in image data. While calculating the evaluation value from time to time by a predetermined evaluation function based on, while the evaluation value is increasing, the rotation of the lens barrel in a predetermined direction and the calculation of the evaluation value are continued, and the evaluation value is The method for adjusting the focus of a camera in an intercom apparatus with a camera according to claim 1, wherein a pre-step of setting the evaluation value immediately before the decrease as the threshold value is performed when the intercom equipment with a camera is adjusted. An adhesive for ejecting an adhesive as the fixing device to the adjusting device is provided with a notch portion for exposing the screwed portion of the lens barrel at a screwed portion of the lens holder with the lens barrel. Equipped with a dispenser,
The method of adjusting the focus of a camera in an interphone device with a camera according to claim 1 or 2, wherein in the fourth step, the adhesive is discharged toward the cutout portion.

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