JPH02234335A - High-speed frame pickup camera - Google Patents

Abstract

PURPOSE:To acquire output images of high resolution so as to enable frames to be picked up at high speed by adopting the method of impressing a pulse voltage upon a MCP. CONSTITUTION:An optical image focused on a photoelectric surface 4 is converted into its corresponding photoelectron image which is refocused on the input surface of a MCP 212 by paired focusing electrodes 107 while being arranged on the input surface of the MCP 212 in the form of a time series by paired deflecting electrodes 109. Then, a pulse voltage is impressed upon the MCP 212 to be set in its activated condition in accordance with a timing when each photoelectron image is arranged on the input surface of the MCP 212 so that plural frame-portion sheets of output images may be acquired on a fluorescent screen 111. Since the pulse voltage can be accordingly impressed upon the MCP 212 to make a high-speed shuttering action, the frames of high resolution output images can be picked up at high speed without substantially causing any fading of images given through electron lenses, such as the paired focusing electrodes 107 and the like even if a rounding is present in the waveform of voltage for making a shuttering action. This makes it possible to acquire a high-speed frame pickup camera which permits picking up the frames at high speed without causing any fading of the output images even in a short exposure time.

Description

[Detailed description of the invention]

[Field of Industrial Application] The present invention relates to an electronic high-speed time-lapse camera with short time intervals and high shutter speed, suitable for continuous photographing of objects, images, etc. whose shapes and brightness change rapidly. rPrior Art] In order to observe the temporal movement of a two-dimensional observation target,
A high-speed camera is used that captures multiple time-lapse images by operating the A-speed shutter at short time intervals. Such cameras include mechanical high-speed cameras that mechanically rotate optical elements such as mirrors and prisms at high speed to obtain multiple time-lapse images, and mechanical high-speed cameras that obtain multiple time-lapse images by mechanically rotating optical elements such as mirrors and prisms. Electronic high-speed cameras are known that capture images for only that amount of time. Generally speaking, the latter type of electronic high-speed camera provides shorter imaging intervals and faster shutter speeds than mechanical high-speed cameras; High-speed cameras are suitable. FIG. 5 is a sectional view showing an electronic high-speed camera using a conventional image tube (time-lapse tube). First, the structure and operation of the image tube in normal operation will be explained based on FIG. As shown in FIG. 5, when the optical image of the object to be observed 1 is formed by the optical lens 2 on the photocathode 4 on the inner surface of the optical window 3 of the image tube, the optical image is transmitted from the photocathode 4. Photoelectrons are emitted depending on the shape and brightness. Therefore, the optical image of the observation object 1 is converted into a photoelectron image 5 in vacuum of the very surface of the photocathode 4 . Each portion of the converted photoelectron image 5 has a number of photoelectrons proportional to the brightness of each portion of the photoelectron corresponding to that portion, and the photoelectron image 5 is defined as a distribution of the number of these photoelectrons. A negative high voltage (Vκ) of direct current is applied to the photocathode 4, and a negative high voltage of direct current is applied to the mesh (acceleration) electrode 6 provided toward the inside of the image tube from the photocathode 4. Regarding the voltage, a positive voltage (Vm) is applied from the photocathode 4. Therefore, the photoelectron group forming the photoelectron image 5 is accelerated and moves in the direction of the mesh'R pole 6 due to the potential difference between the charging surface 4 and the mesh electrode 6, and passes through the mesh electrode 6. and proceeds in the direction of the focusing electrode 107 and the anode 108. A negative high DC voltage from the positive direction is applied to the focusing electrode 107 from the photocathode 4, and the anode 1
Since OV (ground potential) is applied to 08, the group of photoelectrons transmitted through the mesh electrode 6 is deflected to the deflection electrode 1 09a.
, 1 09b. On the other hand, the conversion from an optical image to a photoelectron image at the photocathode 4 is performed by 1P
This is done with a very fast response time interval smaller than S (picoseconds). Therefore, photoelectron images corresponding to the shape and brightness of the optical image at each time are generated one after another on the surface of the photocathode 4, and the photoelectron groups constituting this photoelectron image move one after another in the direction of the mesh electrode 6. As a result, a photoelectron beam is generated along the tube axis of the image tube in the direction from the photocathode 4 to the anode 108. Therefore, in each cross section of the photoelectron beam perpendicular to the tube axis, two-dimensional information about the shape and brightness of the optical image at each time is converted into a spatial density of photoelectrons and exists. Further, deflection electrodes 109a are attached to the various surfaces along the tube axis.
, 1091) toward the photocathode 4 side, two-dimensional information of the optical image at each time exists in each cross-section sequentially from earlier to later times, and these two-dimensional information It will sequentially flow into the deflection electrodes 1 09a and 1 09b. From these facts, the two-dimensional information of each cross section is
It can be seen that if they are arranged sequentially on top of 11 at appropriate intervals so that they can be distinguished, a plurality of time-series frame-by-frame images can be obtained. Note that the photoelectron group has various energies of about 0 to several eV when emitted from the photocathode 4, and is emitted at various angles with respect to the photocathode 4. Although this energy is lower than the energy obtained when the electron group is accelerated to the anode 108, for example, about 10 keV, the photocathode 4
For example, in FIG. 5, A of the photoelectron image 5
A group of photoelectrons forming a point is connected to the deflection electrodes 109a, 10
The question arises as to whether or not it will spread out as it accelerates in the direction of 9b, resulting in a blurred image. However, even if there are variations in the energy and traveling direction of the photoelectrons, an appropriate voltage higher than the voltage on the photocathode 4 is applied to the focusing electrode 107 to form an electron lens in this part. Since the spread photoelectron group can be converged to the corresponding point A' on the fluorescent surface 111, the same problem does not arise. The formation of this photoelectron image is shown in FIG. 5 using electron trajectories. Image formation on the fluorescent surface 111 is such that photoelectrons at point A1B of the photocathode 4 pass along photoelectron trajectories indicated by ρ and ρ' in FIG. 5, corresponding to points A' and B' on the fluorescent surface 111. Form an image. When the image tube is operated normally, the pair of deflection electrodes 109a and 109b are kept at ground potential (OV), so that the deflection electrodes 109a and 109b do not affect the trajectory of photoelectrons. The group of photoelectrons focused on the fluorescent surface 111 impacts the fluorescent surface 111 at a speed of 1, so that light is emitted and an output image corresponding to the input optical image is obtained. However, when the change in the input light image exceeds the response speed of the fluorescent material of the fluorescent surface 111, the images formed on the fluorescent surface 111 will overlap, making it impossible to display them as independent images. Therefore, in normal operation, the range in which the movement of the input light image can be observed from changes in the output image is limited by the characteristics of the fluorescent material and the responsiveness of the eye. Next, I will explain the spinning top dance movement. When the image tube performs normal operation without taking time-lapse images, as described above, a DC negative roaring voltage (Vk) is constantly applied to the photocathode 4, and the deflection electrodes 109a, 1
Ov is applied to 09b, and the deflection electrodes 1 09a , 1
09b is designed not to affect the trajectory of photoelectrons. On the other hand, during the time-lapse operation, the voltage applied to the photocathode 4 and the deflection electrode 109a or 109b is changed,
An output image of a stop-motion image is obtained on the fluorescent surface 111. FIG. 6(A) shows the voltage of the photocathode 4 during the time-lapse operation, and FIG. 6(B) shows the deflection electrode 109a synchronized with the voltage.
The deflection voltage applied to 1109b is shown. A voltage W1 of a rectangular wave pulse train is applied to the photocathode 4, and a stepped voltage W3 is applied between the deflection electrodes. First, attention will be paid to the photocathode 4 and the mesh electrode 6. The same negative high DC voltage (vIm) as in the normal operation described above is applied to the mesh electrode 6. Figure 6 (
In A), it is shown as W2-V■. Light '1 and 4 G. t, voltage Vk'(Vk'>
A rectangular wave pulse voltage W1 with a period T2 consisting of a voltage Vk (Vk < Vs) and a voltage Vk (Vk < Vs) is applied. The voltage W2 (-Vl) of the mesh electrode 6 and the voltage W+ of the photocathode 4 (Vk'> Vl > Vk)
'One-child type shatter action is performed. When the voltage W+ of the photocathode 4 is Vk', it is higher than the voltage W2 (=VII1) of the mesh electrode 6, so the photoelectrons emitted by the charging surface 4 are repelled by the potential of the mesh electrode 6, and the output image is I can't get it. When the voltage W1 of the photocathode 4 is Vk, it is lower than the voltage W2 (-Vl) of the mesh electrode 6, so the photoelectrons emitted from the photocathode 4 are accelerated by the potential of the mesh electrode 6 and are emitted into the space of the focusing electrode 107. It will be done. The period T1 during which the voltage W1 of the photocathode 4 is Vk corresponds to the exposure time of a normal camera. In the case of an image tube, since photoelectrons are used instead of light, this period will be referred to as exposure time hereinafter. Further, the period T2 of the rectangular wave pulse train of the voltage W1 corresponds to the exposure interval (time interval of time-lapse images obtained chronologically). Regarding one deflection electrode 109b, OV( ground potential), and the deflection electrode 109a
For voltage W3 of the stepped waveform shown in FIG. 6(B),
Apply. When the photoelectron beam passes between the deflection electrodes 109a and 109b, it is deflected in proportion to the voltage between the deflection electrodes To9b (hereinafter referred to as deflection voltage), and the fluorescent light 11
Reach 1. Here, FIG. 7 shows the positional relationship of output images obtained in the case of three-frame imaging. As shown in FIG. 6(B), at times t1 to t1' when VD+ is applied as the deflection voltage, the photoelectrons corresponding to the optical images reaching the space between the deflection electrodes 109a and 109b are An image is formed at the position indicated by the output *(1) of the fluorescent surface 111 in FIG. Further, at times t2 to 12' when VD2 (-0) is not applied as the deflection voltage, the deflection electrodes 109a,
The photoelectrons corresponding to the optical image that reached the space of 109b are
Without being deflected, it is imaged at the position shown by the output image (2) of the fluorescent surface 111 in FIG. Also, when VD3 is applied as the deflection voltage (from time t3 to

In (3), the photoelectrons corresponding to the optical image reaching the space of the deflection electrode 109 are imaged at the position indicated by the output image 3 of the fluorescent surface 111 in FIG. The output image formed by the photoelectron imaging as described above is recorded by an optical camera 113 shown in FIG. 5 with the shutter open, for example, from the time when these arrays start to the time when they end. The above-mentioned exposure time T1 has the same important meaning as the exposure time in the case of a normal optical camera, and if the exposure time T1 is too long compared to the time when the light image changes, the period of the synchronization T2 will be interrupted by fluorescence. Since the light image corresponding to the input light image continues to be emitted at the same position on the surface 111, the moving light images overlap, resulting in a blurred image. If the exposure time T1 is too short, the light emitted on the fluorescent surface 111 will be interrupted in just a moment, and the supply of photoelectrons carrying optical information will be cut off, resulting in a dark output image. For this reason, a long exposure time T1 is usually selected, taking into consideration the rate of change of the input light image, as long as the image does not become blurred. In other words, the input light image remains substantially stationary during the exposure time T1 selected in this way. The deflection electrodes 109a and 109b have the role of arranging photoelectron images corresponding to respective exposure times on the fluorescent surface 111. During the exposure time T1, the deflection voltage must remain constant at least for that period of time in order to cause the photoelectron beam to flow into the same location on the phosphor surface. In the photograph 11Ei 113, an output image produced by the light emitted from the fluorescent light 111 is recorded on a film. In this example, three frames of output images are recorded. [Problems to be achieved by the invention] As mentioned above, conventional electronic high-speed time-lapse cameras can achieve high-speed time-lapse photography that cannot be achieved with optical devices;
This camera also has the following limitations. That is, when the exposure time T1 is very small, such as several tens of nanoseconds (nanoseconds) or less, the voltage W1 shown in FIG. 8 does not have a sharp rising and falling waveform as shown in FIG. A voltage W4 having a distorted waveform as shown is applied to the photocathode 4. If the voltage on the photocathode 4 is more negative than the voltage on the mesh electrode 6, the photoelectron beam passes through the mesh electrode and causes the fluorescent surface to emit light. Therefore, as can be seen from FIG. 8, even when the voltage of the photocathode 4 is not equal to (Vk) and corresponds to a slope part in the middle of the waveform, the fluorescent light 111 is caused to emit light. Further, the focusing electrode 107 correctly forms a photoelectron image on the fluorescent surface only when the potential of the photocathode 4 is equal to Vk, and blurs it otherwise. Therefore, if the voltage W4 has a waveform as shown in FIG. 8, the output image will be blurred. Furthermore, even with such a corrupted waveform, the voltage W4 requires an amplitude of several tens to several i oov. Therefore, when the exposure time T1 is shorter than several Qns, it is impossible to construct a circuit that generates an ideal voltage as shown in FIG. Therefore, the conventional high-speed time-lapse camera that performs shutter motion by applying a pulse voltage to the photocathode 4 has a problem in that blurring cannot be prevented when the exposure time is short. A type of so-called shatter image tube is one that applies a short pulse voltage to a microchannel plate (hereinafter abbreviated as MCP) to perform shatter motion, and obtains an image with an extremely short exposure time of several hundred seconds or less. There is. An example of this shatter image tube is shown in FIG. The shatter image tube shown in FIG. 9 forms a xmm image on the fluorescent surface 111, and is operated by an MCP 212 at high speed. The MCP 212 has a photocathode 214 made of Au or CsI, as shown in FIG. 9(B) when enlarged. In addition, the code 216 in FIGS. 9(A) and (B)
, 218 are output side and input side electrodes, and 219 is a window made of Be. When operating the MCP 212 in a shutter operation, as shown in FIG.
6, and only while this pulse voltage is applied, the input side charging surface 2 of the MCP 212
A photoelectron image emitted from the MCP 212 is multiplied by the MCP 212 and appears on the output side. On the other hand, when no voltage is applied to the electrode 216, there is no output from the MCP 212. However, although the conventional shatter image tube shown in Figure 9 can obtain a fast shatter speed, it can only obtain a single photoelectron image and cannot capture continuously changing images. It was impossible to know the state of change of things. The present invention has been made in view of the above-mentioned conventional problems, and
To provide a high-speed time-lapse camera capable of taking high-speed time-lapse images without blurring an output image even with a very short exposure time by utilizing the high-speed shutter effect produced by applying a pulse voltage to an MCP. The task is to

[i! Means for Accomplishing the Problem 1 The present invention provides a high-speed time-lapse camera that includes an optical window, a photocathode attached to the inner surface of the optical window, a focusing electrode, an anode, a deflection electrode, a microchannel plate (MCP), and an output window. a time-lapse tube having a fluorescent surface and an output window attached to the inner surface of the tube; a DC high-voltage power source for driving the time-lapse tube; and a deflection voltage generation source for applying a deflection voltage to the deflection electrode; A configuration consisting of a pulse voltage generation source for applying a pulse voltage to the microchannel plate,
The optical image formed on the charging surface is converted into a photoelectron image, and the photoelectron image is reimaged on the microchannel plate by the focusing electrode and time-series on the input surface of the microchannel plate by the deflection electrode. The photoelectron images are arranged on the input surface of the microchannel plate, and in accordance with the timing when each photoelectron image is arranged on the input surface of the microchannel plate, a pulse voltage is applied from the pulse voltage generation source to the microchannel plate to activate it, and the output fluorescence is activated. The above object has been achieved by providing means for obtaining a plurality of output images on a surface. Further, in the present invention, the deflection voltage generation source and the pulse voltage generation source can be activated at appropriate timing. Further, in the present invention, a plurality of the microchannel plates may be provided corresponding to one or more output images. [Operation of the invention] In the present invention, in a time-lapse camera, an optical image formed on the photocathode of a time-lapse tube is converted into a photoelectron image, and the photoelectron image is reproduced on the MCP input surface using a focusing rod. At the same time as imaging, the photoelectron images are arranged in time series on the MCP input surface using a deflection electrode, and a pulse voltage is applied to the MCP at the timing when each photoelectron image is arranged on the MCP input surface to activate it. to obtain a plurality of output images on the fluorescent surface. Therefore, since it is possible to apply a pulse voltage to the MCP to cause the shatter action to occur at high speed, even if there is an rounding of the voltage waveform that causes the shatter action, for the following reason,
There is virtually no blur in images generated by electron lenses such as focusing electrodes, and high-resolution output images can be captured at high speed. That is, the shatter effect of MCP is as shown in Fig. 3.
This occurs because the electron multiplication factor of P varies greatly depending on the voltage applied to the MCP. For example, M.C.
When the voltage applied to P is Ov, the electron multiplication factor is less than 1, 10
', and on the other hand, at 700v, it changes 500 times. Therefore, Qv can be said to be in a substantially OFF state, and the voltage Qv
As the value increases, the multiplication rate increases rapidly and turns ON.
state. For example, if the exposure time of the electronic shutter is short, such as 10 ns, the waveform of the pulse voltage input to the MCP will be distorted from the ideal rectangular wave, but there is a +5 kV waveform on the fluorescent surface. Since a positive high voltage is applied and the MCP output surface and the fluorescent surface are close to each other, the M
Even if there are multiplied electrons emitted from the MCP during the rise or fall of the pulse voltage applied to the CP output surface, no blurring occurs in the ζ output image. Incidentally, by activating the deflection voltage generation source and the pulse voltage generation source at appropriate timing, it is possible to reliably obtain a plurality of frame-by-frame output images. Furthermore, if a plurality of microchannel plates are provided corresponding to one or more output images, as will be described in detail later,
There is no need to use an expensive and large MCP, the rounding of the voltage waveform applied to the MCP is reduced, and background noise does not occur.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. First, a first example will be described. This first embodiment is a high-speed time-lapse camera configured as shown in FIG. a generation source 220, a pulse voltage generation source 222 for applying a pulse voltage to the MCP (microchannel plate) 212, and the deflection voltage generation source 2.
20 and the pulse voltage generation source 222 at a desired timing to obtain a plurality of output images on the fluorescent surface 111, a half mirror 224, a lens 226, and P.
A trigger signal generating section 232 consisting of an IN photodiode 228 and a delay circuit 230 is provided. In addition, the first
In the figure, reference numeral 234 indicates the deflection voltage generation source 220.
A second delay circuit 236 delays the trigger signal output from the pulse voltage source 222 by a predetermined time and transmits the delayed trigger signal to the pulse voltage generation source 222.
7,! This is a DC high voltage power supply for applying a DC high voltage to the optical surface 111. Other configurations include the conventional electronic high-speed camera shown in Figure 5 above and the MC shown in Figure 9 above.
Since it is substantially the same as P, the same parts are given the same numbers and the explanation thereof will be omitted. The operation of the first embodiment will be explained below. In order to perform the electronic shutter operation, in the conventional high-speed camera shown in FIG. 5 above, a shutter voltage as shown in FIG. 6 (A) above is applied to the photocathode 4. On the other hand, in this embodiment, the shutter voltage is not applied to the photocathode 14, but a pulse voltage is applied to the MCP to perform the shutter operation. In this embodiment, the operations other than this shutter operation are the same as the & speed camera shown in FIG. 5 above. In the fast time-lapse camera according to the first embodiment shown in FIG.
, 5kv and -8.7kv are applied to the focusing electrode 107, respectively, and the anode 108 is set to Ov (ground potential). First, the deflection electrode 109a. When no voltage is applied between 1 and 09b, the object to be observed 1 is imaged by the lens 2 through the optical window 3 onto the photocathode 4, similar to the columnar camera shown in FIG. Then, a photoelectron image is emitted from the charging surface 4 in response to the image formation. The emitted photoelectron image is re-imaged onto the input surface of the MCP 212. Further, the deflection electrodes 109a and 109b are shown in FIG.
) is supplied from the deflection voltage generation source 220, and photoelectron images are arranged on the manual surface of the MCP 212 as shown by symbols <<1> to (3) in FIG. If no voltage is applied to the MCP 212 at this point, the M
The CP212 does not perform a shutter operation, and even if the photoelectron images are arranged in chronological order on the MCP212 manual surface, no output brass is obtained. Therefore, deflection electrode 1 09a 11 09b
When applying a stepped voltage as shown in Fig. 2 <8>, the time T2 (%) during which the applied voltage is flat is
In the example, a pulse voltage with a half-width lQns and a peak voltage of +700V is applied from the pulse voltage generation source 222 to the MCP output electrode 2 at the timing shown in FIG.
16. As a result, M
The photoelectron image distributed on the CP input surface 214 is doubled, and the M
Emitted from the output side of CP212. The electronic shutter operation is performed in the manner described above. On the other hand, the fluorescent surface 111 is supplied with +5
Since a DC voltage of kv is supplied, the multiplied photoelectron current emitted from the output side of MCP 212 is transmitted to the fluorescent surface 1.
11 to generate light emission and form an output image. Therefore, a voltage as shown in FIG. 2(B) is applied to the deflection electrode 10.
9a, 109b, MCP212
By applying the pulse voltage shown in FIG. 2(A) to , three output images are obtained. Note that the shatter effect of the MCP 212 is such that the electron multiplication factor of the MCP 212 is as shown in FIG.
This occurs because the voltage varies greatly depending on the voltage applied to the voltage. For example, the voltage applied to the MCP212 is
In Ov, the electron multiplication factor is 10゛2, which is less than 1, while 7
At 00v, the change is 500 times. Therefore, Ov can be said to be substantially in an OFF state, but as the voltage increases from Qv, the multiplication factor rapidly increases and becomes an ON state. Also, when the MCP 212 is used for shutter operation, if the exposure time is as short as 10 ns, the pulse voltage applied to the photocathode as shown in FIG.
The waveform of the pulse voltage applied to P212 is rounded from an ideal rectangular wave. However, a high voltage of +5kv is applied to the fluorescent surface 111, and the MCP2 1 2 output surface and the fluorescent surface 11
1 are close to each other, so during the rise or fall of the pulse voltage applied to the MCP212 output surface, the MCP212
Even if there are multiplied electrons emitted from the fluorescent surface 111, no blurring will occur in the output image obtained on the fluorescent surface 111. Observing the image of a rapidly changing object at which time is an essential function of a high-speed time-lapse camera. In order to achieve this function, in the embodiment, a trigger signal for activating the deflection voltage generation source 220 at a desired timing is input from the trigger signal generation section 232, and the trigger signal is transmitted via the deflection voltage generation source 220. Trigger signal to 2nd
The delay circuit 234 delays the pulse voltage generation 1[12
22, the MCP 212
A pulse voltage is applied to 12 to obtain a plurality of (three in the embodiment) output images on the fluorescent surface 111. In addition,
If the object 1 to be observed is one that causes high-speed changes due to electrical signals, in addition to taking in a part of the light from the half mirror 224 and using it as a trigger signal in the trigger signal generation section 232, it is also possible to directly trigger the electrical signal. It can be used as a signal to start the deflection voltage generation source 220 and the pulse voltage generation source 222. Next, a second embodiment of the present invention will be described. In this second embodiment, instead of one MCP used in the first embodiment, a small MC is used as shown in FIG.
P is provided corresponding to each output image. In this second embodiment, in order to obtain three output images, M
Three CPs are provided as shown by the reference numerals 212A12128.2120 in the figure, and each of these MCP21 2A
, 212B, and 212C, delay circuits 234A. 234B. 234C, and each MCP21 2A by the transmitted trigger signal,
21 2B, 212C are provided with pulse voltage generation sources 222A1222B, 222G for applying pulse voltages, and these pulse voltage generation sources 11222A, 222
B and 222C are MCP212A and 21281, respectively.
The output image is formed on the fluorescent surface by controlling the shutter timing of 212C. This second embodiment uses a small MCP and is economical because it does not use a large and expensive MCP as in the first embodiment. Also, small and large MCPs are large MCPs.
Since the floating capacitance i is smaller, the rounding of the voltage waveform applied to the MCP becomes smaller. Although it is possible with the present invention to avoid blurring of the output image even if there is an rounding in the voltage waveform, if the rounding is made smaller, the exposure time can be further reduced. It is desirable to adopt the example. In the first embodiment, as shown in FIG. 1, the MCP is turned on three times to obtain three output images at different positions. For example, if we focus on the location (1), it is clear that the photoelectric The surface image is focused on that position only once, and the other two times it moves to the positions (2) and (3), and the photoelectrons from the photocathode 4 do not collide, but the stray light causes the focusing electrode 107 There are electrons emitted from the photocathode 4 and electrons emitted by stray light from areas other than the light-emitting surface of the photocathode 4, although they are small. When the MCP 212 is turned on, these background electrons are multiplied and emit light on the output surface, causing noise. In contrast, the second embodiment has the advantage that each MCP is turned ON only once in synchronization with the timing at which a photoelectron image is formed, so that such background electron noise does not occur. have In addition, in the first and second embodiments, an electrostatic focusing method using the focusing electrode 107 was adopted as a method for focusing photoelectrons, but the stop-motion tube implementing the present invention is limited to such a configuration. For example, it is also possible to use an electromagnetic focusing method using a focusing coil. Further, although the mesh electrode 6 was used in the stop-motion tubes of the first and second embodiments, this mesh electrode is not necessarily required when carrying out the present invention. Effects of the Invention 1 As explained above, according to the present invention, a method is adopted in which a pulse voltage is applied to the MCP in order to perform a high-speed shatter action in a high-speed stop-motion camera. Even if there is waveform distortion, there is virtually no blurring of the image caused by the electro-optical lens, resulting in the excellent effect of obtaining a high-resolution output image and enabling high-speed distortion. .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view, including a partial block diagram, showing the overall configuration of a high-speed time-lapse camera according to the first embodiment of the present invention. FIGS. Figure 3 is a diagram showing an example of the waveform of a pulse voltage for performing the pulse voltage waveform and the waveform of the deflection voltage applied to the deflection electrode. FIG. 4 is a block diagram including a cross-sectional view of essential parts, showing in detail the vicinity of the MCP according to the second embodiment of the present invention. FIG. 5 is a cross-sectional view showing an example of the configuration of a conventional electronic speed camera. 6(A) and (B) are diagrams showing examples of the shutter voltage waveform and deflection voltage waveform to the high-speed camera, and FIG. 7 is a diagram showing an example of an output image taken time-by-frame by the high-speed camera. 8 is a diagram showing an example of the shutter voltage in the same dull state. 911 (A>, <<8>>) is an example of the configuration of a conventional camera using MCP as a single-shot shutter. It is a sectional view of the main parts showing 1... object to be observed, 3... optical window,
4... Photocathode, 107... Focusing electrode, 108... Anode, 1 09a. 1 09b --- Deflection electrode, 111
... Fluorescent surface, 110 ... Output window, 21
2, 21 2A, 21 2B, 21 2G...MCP
．． 220... Stepped deflection voltage generation source, 222... Pulse voltage generation source, 224... Half mirror, 226... Lens, 228... PIN photodiode, 230... Delay circuit, 232... - Trigger signal generation section, 234... second delay circuit, 236... DC high voltage power supply.

Claims (3)

[Claims] (1) an optical window, a photocathode attached to the inner surface of the optical window;
a time-lapse tube having a focusing electrode, an anode, a deflection electrode, a microchannel plate, a fluorescent surface attached to the inner surface of the output window, and an output window; a DC high-voltage power source for driving the time-lapse tube; and the deflector. a deflection voltage generation source for applying a deflection voltage to the electrode; a pulse voltage generation source for applying a pulse voltage to the microchannel plate; and converting the optical image formed on the photocathode into a photoelectron image. The photoelectron images are re-imaged onto the microchannel plate by the focusing electrode, and the photoelectron images are arranged in time series on the input surface of the microchannel plate by the deflection electrode, so that each photoelectron image is placed on the microchannel plate. means for applying a pulse voltage from the pulse voltage source to the microchannel plate in accordance with the timing arranged on the input surface to activate it, and obtaining a plurality of output images on the fluorescent surface. A high-speed time-lapse camera characterized by: (2) A high-speed stop-motion camera according to claim 1, characterized in that the deflection voltage generation source and the pulse voltage generation source are activated at appropriate timings. (3) A high-speed stop-motion camera according to claim 1, characterized in that a plurality of said microchannel plates are provided corresponding to one or more output images.