JP7684797B2 - optical equipment - Google Patents

Description

The present invention relates to an optical device.

Conventionally, virtual systems have been used that combine images from an imaging device having an optical device (lens device) with images from computer graphics. In such virtual systems, it is required to enable image synthesis that does not look unnatural even when a user operates the zoom and focus in real time in the optical device. Patent Document 1 discloses an optical device that contributes to image synthesis that does not look unnatural by generating communication data including information about the position of optical members and transmitting it to an external device such as a virtual system.

JP 2006-30656 A

The optical device disclosed in Patent Document 1 generates a pulse train signal related to the amount of displacement of an optical member and transmits it to an external device, but such a pulse train signal is not necessarily advantageous for use in an external device. The present invention aims to provide an optical device that generates a pulse train signal that is advantageous for use in an external device, for example.

The optical device of the present invention is an optical device having a movable optical element, a detection unit that detects the position of the optical element, a communication unit that communicates with an external device, and a processing unit, wherein the processing unit generates information regarding optical characteristics including the angle of view of the optical device based on the position , and generates a pulse train signal corresponding to a cumulative value of the corrected optical characteristics based on the information regarding the optical characteristics and information indicating a standard for communication with the external device for the angle of view , and the communication unit transmits the pulse train signal to the external device.

The present invention can provide, for example, an optical device that generates a pulse train signal that is advantageous for use in an external device.

1A and 1B are block diagrams of a lens apparatus and a virtual system according to a first embodiment. 6 is a flowchart illustrating an example of a process for generating communication data, which is performed by the lens device according to the first embodiment. 5A and 5B are schematic diagrams showing a process of calculating an angle of view in the lens device according to the first embodiment. 5 is a schematic diagram showing communication data generated in the lens device according to the first embodiment. 10 is a flowchart illustrating an example of a process for generating communication data, which is performed by the lens device according to the second embodiment. FIG. 11 is a schematic diagram showing communication data generated in a lens device according to a second embodiment.

The optical device according to this embodiment will be described in detail below with reference to the accompanying drawings. Note that the drawings shown below may be drawn at a scale different from the actual scale in order to facilitate understanding of this embodiment.

[First embodiment]
In a camera equipped with a lens device, a user can capture a desired image by electrically or manually operating a movable optical element in the lens device to perform optical changes such as zooming and focusing.
Meanwhile, virtual systems that combine real-life images captured by an imaging device such as a camera with computer graphics images linked to the real-life images are widely used.
In such a virtual system, the zoom position and focus position of the lens device are received from the lens device, making it possible for an internal computer to generate computer graphics that match the size of the actual image.

In addition, some virtual systems improve tracking performance by receiving information from the lens device in the form of a digital pulse train.
This makes it possible to synthesize images in the virtual system without creating a sense of incongruity, even if the user operates the zoom or focus in the lens device in real time.
Also, a lens device is known that is capable of outputting position information of an optical element provided therein to a virtual system.

Figure 1 shows a block diagram of a lens device 10 and a virtual system 20, which are optical devices according to the first embodiment.

In the lens device 10 according to the present embodiment, a movable optical element is controlled for image capture. An image capture element (not shown) provided in an image capture device receives (captures) an image formed by the lens device 10 according to the present embodiment, thereby capturing an image.
The virtual system 20 (external device) synthesizes a computer graphics image with an image captured by an imaging device including the lens device 10 according to this embodiment. In other words, the virtual system 20 processes image data obtained by the imaging device based on a pulse train signal transmitted from the lens device 10 according to this embodiment.
In this manner, the lens apparatus 10 and the virtual system 20 according to this embodiment form an image synthesis system.

Specifically, the lens device 10 according to this embodiment includes an optical element 101 , a position detection unit 102 (detection unit), a processing unit 103 , a storage unit 104 , and a communication unit 105 .
The virtual system 20 also includes a communication unit 201 , a measurement unit 202 , and a processing unit 203 .

The optical element 101 can change the optical characteristics of the lens device 10 according to this embodiment, such as zoom and focus, by moving (changing its position, being movable).
The position detection unit 102 is connected to the optical element 101 and the processing unit 103, and is configured with a potentiometer, an encoder, etc. that can detect the current position of the optical element 101. Then, the position detection unit 102 outputs the acquired information to the processing unit 103.

The processing unit 103 is connected to the position detection unit 102, the memory unit 104 and the communication unit 105, and generates communication data from information input from the position detection unit 102 and optical information stored in the memory unit 104, and outputs it to the communication unit 105.
The storage unit 104 can store in advance optical information including focal lengths and angles of view corresponding to the zoom positions, focus positions, and the like of the lens device 10 according to this embodiment.
The communication unit 105 is connected to a communication unit 201 provided in the virtual system 20, and transmits communication data regarding optical information (information regarding optical characteristics) of the lens device 10 input from the processing unit 103 to the communication unit 201 of the virtual system 20.

The communication unit 201 is connected to the measurement unit 202 and outputs communication data received from the lens device 10 according to this embodiment to the measurement unit 202 .
The measurement unit 202 is connected to the processing unit 203 , performs measurements to interpret the communication data input from the communication unit 201 , and outputs information obtained from the measurements to the processing unit 203 .
The processing unit 203 synthesizes an image captured by the lens device 10 according to this embodiment with an image using computer graphics, based on the information input from the measurement unit 202 .

By transmitting information about the lens device 10 according to this embodiment to the virtual system 20 in accordance with the above configuration, it is possible to process the image captured by the lens device 10 according to this embodiment.

FIG. 2 shows a flowchart of an example of a process for generating communication data, which is performed by the lens apparatus 10 according to the present embodiment.
This process is periodically executed by the processing unit 103 after the lens apparatus 10 according to this embodiment is started up.

First, in step S101, the position of the optical element 101 is acquired by the position detection unit 102.
In step S102, the position of the optical element 101 acquired in step S101 and the focal length information stored in the storage unit 104 are referenced to acquire the current focal length of the lens apparatus 10 according to this embodiment.
In step S103, the angle of view when focused at infinity is calculated by referring to the focal length of the lens device 10 according to this embodiment acquired in step S102 and the angle of view information stored in the memory unit 104.

3 is a schematic diagram showing the process of calculating the angle of view in step S103. Specifically, a rear principal point P and an imaging plane I are shown in FIG.
Here, when the focal length is f, the image height is h, and the angle of view is 2θ, the angle of view 2θ when focused at infinity is expressed by the following formula (1).

In step S103, a process of calculating the angle of view can be executed using equation (1).
Here, since the image height h can be found from the size of the image sensor provided in the image pickup device, the angle of view 2θ can be calculated using the focal length f as a variable.

The calculation results of the angle of view 2θ corresponding to the focal length f may be stored in advance in the storage unit 104 as a table.
Then, in step S103, the angle of view may be calculated by referring to a table stored in the storage unit 104 from the focal length f acquired in step S102.

In step S104, the angle of view calculated in step S103 is corrected. Specifically, since the angle of view varies depending on changes in the focus position, distortion, principal point position, etc., the angle of view is corrected by referring to correction information from the storage unit 104.
In step S105, a standard required for generating communication data is obtained from the storage unit 104. The standard here refers to a unit for changing communication data related to the angle of view, and indicates information that the communication data is changed every 1°, for example.
It should be noted that this unit is arbitrary, and may be set finer, such as 0.1°, to improve accuracy.

In step S106, communication data for outputting the angle of view calculated and corrected in steps S103 and S104 to the virtual system 20 is generated, that is, the data relating to the angle of view is converted into a pulse train.
Here, the communication data is generated using the following formula (2).
Communication data = angle of view/standard ... (2)

That is, for example, if the angle of view and standard are 12° and 1°, respectively, the communication data will be 12.

4 is a schematic diagram showing the communication data generated in step S106, where the standard for the angle of view is 1°.
Specifically, FIG. 4 shows the A-phase pulse and B-phase pulse, which are the pulse train signal generated in step S106, and the time change of the counter, which is the processing result of the virtual system 20.

For example, as shown in FIG. 4, in the first half region T1 of the time change, an A-phase pulse and a B-phase pulse are each generated three times, with a time lag of half a pulse width (half a pulse) between them so that the B-phase pulse lags behind the A-phase pulse, and then output.
In the latter half region T2 of the time change, A-phase pulses and B-phase pulses are generated four times each, with a time shift of half a pulse width from each other so that the B-phase pulse lags behind the A-phase pulse, and then output.
That is, the lens device 10 according to this embodiment employs a phase difference input method as shown in FIG. 4 when generating communication data.
In other words, in the lens apparatus 10 according to this embodiment, the communication unit 105 transmits, as the pulse train signal, two pulse train signals whose phases differ from each other by π/2.

Here, when (A, B) satisfies any of (U, L), (H, U), (D, H) and (L, D), the count value N of the counter in the virtual system 20 is increased by 1.
Here, U indicates the rising edge of the pulse, that is, the voltage V increases from LOW to HIGH, and D indicates the falling edge of the pulse, that is, the voltage V decreases from HIGH to LOW.
Moreover, H indicates that the voltage V is maintained at HIGH, and L indicates that the voltage V is maintained at LOW.
That is, for example, (A, B)=(U, L) means that while the voltage V of the B-phase pulse is maintained at LOW, the voltage V of the A-phase pulse rises from LOW to HIGH.

In the first half region T1, the counter receives the output of a pulse train consisting of three A-phase pulses and three B-phase pulses that are out of phase with each other, so that the total count value N can be 4 x 3 = 12°.
Similarly, in the latter half region T2, the counter receives the output of a pulse train consisting of four A-phase pulses and four B-phase pulses that are out of phase with each other, so that the total count value N can be 4 x 4 = 16°.

As described above, the lens apparatus 10 according to the present embodiment outputs the absolute value of the angle of view to the virtual system 20. In other words, in the lens apparatus 10 according to the present embodiment, the generated pulse train signal corresponds to the absolute value of the optical characteristic.
The virtual system 20 can receive the current value of the angle of view by resetting the counter until the lens device 10 in this embodiment starts to output the next pulse train, i.e., for example, between the first half region T1 and the second half region T2.

Then, in step S107, the pulse train generated in step S106 is transmitted to the communication unit 201 of the virtual system 20.
In this manner, the lens apparatus 10 according to this embodiment can transmit the position of the optical element 101 to the virtual system 20 in real time.

As described above, the lens device 10 according to this embodiment treats the angle of view as an absolute value in the optical dimension, and is therefore capable of transmitting data regarding the angle of view for real-time image synthesis in the virtual system 20.

[Second embodiment]
FIG. 5 shows a flowchart of an example of a process for generating communication data, which is performed by the lens device according to the second embodiment.
Since the lens device according to this embodiment has the same configuration as the lens device 10 according to the first embodiment, the same members are designated by the same reference numerals and descriptions thereof will be omitted.
Moreover, this process is periodically executed by the processing unit 103 after the lens apparatus according to this embodiment is started up.

First, in the lens device according to this embodiment, the processes of steps S101 to S105 are performed in the same manner as in the lens device 10 according to the first embodiment.
Next, in step S206, the difference between the angle of view calculated and corrected in steps S103 and S104 and the cumulative value of the angle of view in the previous processing is calculated, whereby the calculated angle of view can be converted into a relative value with respect to the angle of view in the previous processing.

Then, in step S207, communication data is generated to output the angle of view calculated in step S206 to the virtual system 20, i.e., the data regarding the angle of view is converted into a pulse train.

6 is a schematic diagram showing the communication data generated in step S207. Note that the standard for the angle of view is 1°, and the initial value of the count value N of the counter is 0.
Specifically, FIG. 6 shows the A-phase pulse and B-phase pulse, which are the pulse train signal generated in step S207, and the time change of the counter, which is the processing result of the virtual system 20.

For example, as shown in FIG. 6, in the first half region T1 of the time change, an A-phase pulse and a B-phase pulse are each generated three times, with a time lag of half the pulse width (half a pulse) relative to the A-phase pulse, and then output.
Next, in the intermediate region T2 of the time change, an A-phase pulse and a B-phase pulse are each generated twice, with a time shift of half a pulse width between them so that the A-phase pulse lags behind the B-phase pulse, and then output.
Then, in the latter half region T3 of the time change, an A-phase pulse and a B-phase pulse are each generated once, with a time shift of half a pulse width from each other so that the B-phase pulse lags behind the A-phase pulse, and then output.
That is, the lens device according to this embodiment employs a phase difference input method as shown in FIG. 6 when generating communication data.
In other words, in the lens apparatus according to this embodiment, the communication unit 105 transmits, as the pulse train signals, two pulse train signals whose phases differ from each other by π/2.

Here, when (A, B) satisfies any of (U, L), (H, U), (D, H) and (L, D), the count value N of the counter in the virtual system 20 is increased by 1.
On the other hand, when (A, B) satisfies any of (L, U), (U, H), (H, D) and (D, L), the count value N of the counter in the virtual system 20 is decremented by one.

That is, in the first half region T1, the counter receives an output of a pulse train consisting of three A-phase pulses and three B-phase pulses that are out of phase with each other, and the count value N increases by 4×3=12.
Since the cumulative value up to the previous time is 0, the total count value N can be obtained as 0+12=+12°.

Next, in the intermediate region T2, the counter receives an output of a pulse train consisting of two A-phase pulses and two B-phase pulses that are out of phase with each other, and the count value N is decreased by 4×2=8.
And, since the accumulated value up to the previous time is 0+12=12, the total count value N can be obtained as 12-8=+4°.

In the latter half region T3, the counter receives the output of a pulse train consisting of one A-phase pulse and one B-phase pulse that are out of phase with each other, and the count value N increases by 4×1=4.
And, since the accumulated value up to the previous time is 0+12-8=4, the total count value N can be obtained as 4+4=+8°.

As described above, the lens apparatus according to this embodiment outputs a relative value of the angle of view to the virtual system 20. In other words, in the lens apparatus according to this embodiment, the generated pulse train signal corresponds to a relative value of the optical characteristic.
The virtual system 20 can receive the current value of the angle of view by maintaining the count value N without resetting the counter until the lens device according to this embodiment starts to output the next pulse train.

In step S208, the pulse train generated in step S207 is transmitted to the communication unit 201 of the virtual system 20.
In this manner, the lens apparatus according to this embodiment can transmit the position of the optical element 101 to the virtual system 20 in real time.

As described above, the lens device according to this embodiment treats the angle of view as a relative value in the optical dimension, and is therefore able to transmit data regarding the angle of view for real-time image synthesis in the virtual system 20 without resetting the counter.

The above describes preferred embodiments, but the invention is not limited to these embodiments and various modifications and variations are possible within the scope of the gist.

10 Lens device (optical device)
101 Optical element 102 Position detection unit (detection unit)
103 Processing section 105 Communication section

Claims (5)

An optical device having a movable optical element, a detection unit that detects a position of the optical element, a communication unit that communicates with an external device, and a processing unit,
The processing unit includes:
generating information about optical characteristics of the optical device, including an angle of view , based on the position ;
generating a pulse train signal corresponding to a cumulative value of the corrected optical characteristic based on information about the optical characteristic and information indicating a standard of communication with the external device for the angle of view;
The optical device according to claim 1, wherein the communication section transmits the pulse train signal to the external device. The processing unit includes:
obtaining a focal length of the optical device based on the position ;
The optical device according to claim 1 , wherein the angle of view is obtained based on the focal length and a size of an image sensor. 3. The optical device according to claim 1 , wherein the communication section transmits, as the pulse train signal, two pulse train signals having a phase difference of π/2 from each other. An optical device according to any one of claims 1 to 3 ,
and an image sensor for capturing an image formed by the optical device. The imaging device according to claim 4 ;
and an external device that processes image data obtained by the imaging device based on the pulse train signal transmitted from the optical device.

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