Camera Tube Research Articles

An Unknown Episode in the Invention of the HARP Camera Tube

An Unknown Episode in the Invention of the HARP Camera Tube

Development of a 18-mm-diameter all-electrostatic Super-HARP tube for HDTV Investigation of its electron optics

We have developed the 18-mm-diameter all-electrostatic Super-HARP camera tube for high-performance handheld HDTV cameras. In designing its electron optics, we focused on high resolution and a wide dynamic range. Through experiments and numerical analysis, we have optimized the beam-limiting aperture of the diode-gun to enlarge the dynamic range, and the shape and arrangement of the pattern electrodes in the focusing and deflection system to improve the resolution. A prototype tube exhibited a dynamic range of at least 800% and maximum resolution of more than 1400 TV lines. The new HDTV camera tube thus achieves a good balance of high resolution and wide dynamic range while being compact.

Progress in HDTV camera tubes

Progress in HDTV camera tubes

468 同一装置による撮像管とCCDの性能比較(第二報)

468 同一装置による撮像管とCCDの性能比較(第二報)

26. 同一装置による撮像管とCCDの性能比較 : 第一報:空間分解能、コントラスト分解能

26. 同一装置による撮像管とCCDの性能比較 : 第一報:空間分解能、コントラスト分解能

Low energy ?-ray events in imaging ?erenkov telescope arrays

One of the major goals in VHE-γ-ray astronomy is to open the energy range below 100 GeV with earthbound detectors. This paper demonstrates a new method for analyzing Cerenkov light of a shower in a Cerenkov telescope array. This method is successful for showers in this low energy regime where previous techniques (e.g. alpha analysis) are not applicable. A Monte Carlo simulation is applied to a system of 19 Whipple type [3, Cawley 1990] Imaging Atmospheric Cerenkov telescopes (IACT), each built as a 10 m diameter reflector and equipped with a 109 photomultiplier tube camera. The energy threshold for a single detector of this type is given [5, Kerrick et al. 1995] as 250 GeV. Analysis of simulated coincident events of the system for those events not having enough light to apply a standard imaging analysis [4, Hillas 1985], leads to a considerably lower threshold of 85 GeV. With a new analysis method of these events it is shown that it should be possible to distinguish between γ-ray induced and proton induced showers. The improvement of sensitivity (Q = figure of merit) of this analysis method is found to be Q=2.9.

In-vivo analysis of angiogenesis and revascularization of transplanted pancreatic islets using confocal microscopy.

A technique to measure angiogenesis and revascularization in pancreatic islets transplanted at the renal subcapsular site in the rat has been developed. In-vivo imaging of the microcirculation of transplanted pancreatic islets was conducted using a confocal scanning laser microscope (CSLM) to achieve optical sectioning through the graft in order to perform a computer reconstruction of the three-dimensional neovascular morphology. Individual islets were harvested by enzymatic digestion of excised pancreas from Fischer 344 rats. Isolated islets were cultured for 24 h, and approximately 300-350 islets were transplanted at the renal subcapsular site of the left kidney in an anaesthetized rat. Six to 14 days post-transplantation, the animal was anaesthetized and prepared for in-vivo imaging of the microvasculature on a Zeiss LSM-10. Optical contrast of the microvasculature was enhanced by the administration of fluorescein-labelled dextran into the circulating blood. The transplant site was identified and serial sections were obtained through the vascular bed at varying z-intervals. Complementary fluorescence video images were also obtained via a silicon intensifier tube camera mounted on the CSLM. At completion of the imaging procedure, the kidney was returned into the body cavity, the area was sutured and the animal was allowed to recuperate for subsequent examinations. Image processing algorithms, such as grey-level thresholding, median filtering, skeletonization and template matching, were applied to compute the vessel density and diameters and extrapolated to measure 3-D vessel lengths and the tortousity index of the neovasculature.

Physical conditions in neutral gas atmosphere of P/Halley (1986 III) on the basis of spectral observations

Abstract On the basis of over 40 spectra of comet P/Halley (1986 III) obtained with the 1 m Zeiss reflector and the image-converter tube camera in Assy physical parameters of cometary gas ( Q is the gas production, τ is the lifetime and ν is the velocity of molecules C 2 , C 3 and CN in the neutral coma) were obtained. The low velocities of the CN molecules compared to the velocities of C 2 and C 3 molecules are probably connected to the presence of the extensive source of parental molecules, from the latter as a result of photodissociation CN molecules being generated (CN-jets, CHON-particles).

Whole-cell patch-clamp recordings from visualized bulbospinal neurons in the brainstem slices

The purpose of this study was to develop a method for electrophysiological characterization of retrogradely labeled bulbospinal neurons in the specific cytoarchitectonic regions in the brainstem slices. Several days after the spinal cord was injected with the carbocyanine dye, DiI, retrogradely labeled bulbospinal neurons were visualized by epifluorescence optics in the brainstem slices with the aid of a silicon intensifier tube (SIT) camera. Labeled somata were routinely seen in the caudal raphe nuclei, rostroventral medial and lateral portions of the medulla, the A5 group and in other medullary sites known to project to the spinal cord. Electrophysiological properties of the DiI-labeled neurons were assessed by whole-cell recordings using micropipettes filled with biocytin. The slices were subsequently processed for dual visualization of biocytin and serotinin or a marker for noradrenergic neurons, tyrosine hydroxylase (TH). The electrophysiological properties of bulbospinal neurons were correlated with their morphology and neurochemical content. This technique may be useful in other areas of CNS for studying morphology, neurochemical content and physiology of retrogradely labeled neurons.

Resolution properties of a 2048×2048 matrix image intensifier‐TV based digital radiography system

Spatial resolution properties of a 2048 x 2048 matrix image intensifier (II) TV based real-time digital radiography (DR) system were investigated. The presampling modulation transfer function (MTF), which includes the unsharpness of the detector and the blurring effect of the sampling aperture, was measured by a slit method. Also determined was the limiting resolution using a bar pattern. It was found that, the spatial resolution in this system is substantially improved relative to previous II-TV based DR systems, and is comparable or even superior to that in a computed radiography system depending on the imaging plate employed. However, the presampling MTF for 2048 x 2048 matrix is comparable to that for 1024 x 1024 matrix in this DR system, because the same sampling aperture is assumed to be used for both matrices. Even under these conditions obtained the improved clinical image since the Nyquist frequency is doubled for 2048 x 2048 matrix. It should be noted that the resolution property in the II-TV based DR system depends on the signal current from the TV image pickup tube (level of image pixel value) and also on the size of the iris in the TV lens. We must pay attention to these parameters when acquiring clinical images and evaluating the resolution properties. Finally, it was demonstrated that smaller focus than that used in a screen-film system can be employed in the DR system due to its high sensitivity, so the geometric unsharpness can be reduced. Therefore, the image resolution of our system was found to be superior to a screen-film system at some geometric magnification factors.

26. 同一装置による撮像管と CCD の性能比較 : 第一報空間分解能、コントラスト分解能(第 22 回秋季学術大会一般研究発表予稿)

26. 同一装置による撮像管と CCD の性能比較 : 第一報空間分解能、コントラスト分解能(第 22 回秋季学術大会一般研究発表予稿)

143. CCD カメラと撮像管による画像変化(撮影技術-CCD カメラ)

143. CCD カメラと撮像管による画像変化(撮影技術-CCD カメラ)

Overview of laser microbeam applications as related to antibody targeting.

Laser-based microscopic systems (laser microbeams) are becoming popular tools for investigating various aspects of molecular and cellular biology (1). Depending on the wavelength, energy, and beam geometry employed, laser microbeams can be used for fluorescence excitation, microsurgery, cellular ablation, or micromanipulation of cells and organelles. The use of antibodies permits the targeting of specific antigens or cell types for analysis or treatment. Integrating a laser, microscope, and detection system (camera or photomultiplier tube) with a personal computer creates a workstation capable of controlling data acquisition parameters and performing subsequent data analysis. An example of one such workstation is shown in Fig. 1.

ハイビジョン用１インチ全静電型ＨＡＲＰ撮像管

We propose that high performance HDTV camera tubes be made by combining new one-inch all-electrostatic electron optics with a High-gain Avalanche Rushing amorphous Photoconductor (HARP). Numerical analysis of electric fields and other experimental data indicated that sensitivity could be increased by making a thicker target, that the dynamic range could be increased by designing the diode gun to have a suitable limiting aperture and that resolution could be increased with a unique new configuration of electron optics. A new tube based on these concepts has a maximum sensitivity 32 times that of standard Saticons. Its amplitude response at 800 TV-lines in the ITE-AR chart is 45% at the picture center and is 40% for the average of the four picture corners. Operation with a large signal-current and a higt signal-to-noise ratio results in the highest picture quality ever attained.

Iodine filter imaging system for subtraction angiography using synchrotron radiation

A new type of real-time imaging system was developed for transvenous coronary angiography. A combination of an iodine filter and a single energy broad-bandwidth X-ray produces two-energy images for the iodine K-edge subtraction technique. X-ray images are sequentially converted to visible images by an X-ray image intensifier. By synchronizing the timing of the movement of the iodine filter into and out of the X-ray beam, two output images of the image intensifier are focused side by side on the photoconductive layer of a camera tube by an oscillating mirror. Both images are read out by electron beam scanning of a 1050-scanning-line video camera within a camera frame time of 66.7 ms. One hundred ninety two pairs of iodine-filtered and non-iodine-filtered images are stored in the frame memory at a rate of 15 pairs/s. In vivo subtracted images of coronary arteries in dogs were obtained in the form of motion pictures.

143. CCD カメラと撮像管による画像変化(第 21 回秋季学術大会一般研究発表予稿)

143. CCD カメラと撮像管による画像変化(第 21 回秋季学術大会一般研究発表予稿)

Growth and melting processes of semiconductor crystals observed by live X-ray topography

Using synchrotron radiation, dynamic X-ray observation of defects in crystals has been made easily with an X-ray sensing television camera tube having a resolution of 6μm. The observation led to understanding of origins and behaviour of point defects as well as dislocations at the melting point. The usefulness of such live topography is demonstrated by the experimental results.

Photoconductive Imaging Using CuInSe2 Film

This paper describes an application for the first time of a vidicon type pickup tube using a chalcopyrite-type semiconductor copper-indium-diselenide (CuInSe2) film as a target for the image sensor. The fabricated sensor shows the horizontal resolution of 600 TV lines indicating that CuInSe2 is one of promising materials for television image pickup device with the high resolution.

高感度ＣｄＴｅ光導電膜を用いたビジコン型Ｘ線イメージセンサ

A one-inch X-ray vidicon (imaging camera tube) with a polycrystalline cadmium telluride (CdTe) photoconductive target has been developed. This vidicon has a 10.5μm thick CdTe layer deposited by RF sputtering and can attain an X-ray signal current of about 200 nA/cm2 for 2.58 mC/kg/min (10R/ min). This value is higher than the 45 nA/cm2 of conventional PbO X-ray vidicons. The dark current is about 5 nA/cm2 at a target voltage of 35 V at room temperature. The resolution of the device exceeds 251p/mm (20μm). In addition, by using a sputtering technique which can obtain large and uniform film, simultaneous deposition of many conventional and large vidion targets can easily be performed.

X-ray imaging camera tube using sputter-deposited CdTe/CdS heterojunction

CdTe heterojunction devices have been fabricated for the first time by an RF sputter deposition method for application to X-ray imaging sensors. The electrical resistivities of sputter-deposited polycrystalline CdS and CdTe films are greater than 10/sup 6/ Omega -cm and 10/sup 9/ Omega -cm, respectively. The fabricated CdS/CdTe heterojunction sensor shows a good diode characteristic and a high sensitivity to X-ray radiation. An X-ray imaging camera tube consisting of CdS/CdTe heterojunction photoconductive target shows three times larger responsivity to X-rays than the conventional PbO X-ray tube. The dark current density of the device is observed to be lower than 10 nA/cm/sup 2/ at 20 V target voltage at room temperature. >