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The time-to-digital converter (TDC) implemented in a field-programmable-gate-array has garnered widespread attention due to its flexibility and high-performance capabilities. However, issues such as non-uniformity, the bubble in the tapped delay line, and the presence of certain ultra-wide delay units can significantly compromise the precision and nonlinearity of the TDC. In this paper, we propose a high-precision TDC in an Elitestek Ti60 FPGA, effectively eliminating the adverse effects of non-uniformity, the bubble, and certain ultra-wide delay units. The TDC is constructed with a 318-stage delay chain and operates at a low system clock frequency of 150 MHz. The least significant bit (LSB) of the TDC is 21.92 ps. The differential nonlinearity (DNL) is between (−0.976, 1.615) LSB and the integral nonlinearity (INL) is between (−1.446, 2.678) LSB. The TDC achieves a root-mean-square error of 14.783 ps when utilized for measuring various time intervals. [ABSTRACT FROM AUTHOR]

Dielectric breakdown is an example of a natural phenomenon that occurs on very short time scales, making it incredibly difficult to capture optical images of the process. Event initiation jitter is one of the primary challenges, as even a microsecond of jitter time can cause the imaging attempt to fail. Initial attempts to capture images of dielectric breakdown using a gigahertz frame rate camera and an exploding bridge wire initiation were stymied by high initiation jitter. Subsequently, a novel optical delay line apparatus was developed in order to effectively circumvent the jitter and reliably image dielectric breakdown. The design and performance of the optical delay line apparatus are presented. The optical delay line increased the image capture success rate from 25% to 94% while also permitting enhanced temporal resolution and has application in imaging other high-jitter, extremely fast phenomena. [ABSTRACT FROM AUTHOR]

The implementation of attosecond photoelectron–photoion coincidence spectroscopy for the investigation of atomic and molecular dynamics calls for a high-repetition-rate driving source combined with experimental setups characterized by excellent stability for data acquisition over time intervals ranging from a few hours up to a few days. This requirement is crucial for the investigation of processes characterized by low cross sections and for the characterization of fully differential photoelectron(s) and photoion(s) angular and energy distributions. We demonstrate that the implementation of industrial-grade lasers, combined with a careful design of the delay line implemented in the pump–probe setup, allows one to reach ultrastable experimental conditions leading to an error in the estimation of the time delays of only 12 as over an acquisition time of 6.5 h. This result opens up new possibilities for the investigation of attosecond dynamics in simple quantum systems. [ABSTRACT FROM AUTHOR]

A method of frequency-segmented power amplification using multiband radio frequency (RF) amplifiers was proposed to generate stable and arbitrary high-voltage pulses. The concept behind this method is that an arbitrary pulse with a specified duration and sharp edges can be reconstructed using only several frequencies, and most of the power is concentrated on the fundamental frequency. The high-voltage pulse can, therefore, be obtained by amplifying each segmented frequency and then combining it with the RF power combiners. To correct the frequency-dependent group delays and gain of the amplifier circuit and to perform fine-tuning of the pulse structure, a seed pulse is divided into several lines that have bandpass filters, variable delay lines, variable power attenuators, and main RF amplifiers. A prototype pulse amplifier was designed and fabricated based on this method to generate rectangular pulses for the electron beam chopper of an x-ray free-electron laser injector. Flat and stable pulses with a 2 ns width of 0.2 kV height, peak-to-peak flat top of 0.8%, and route-mean-squared peak jitter of less than 0.2% were successively generated in both single- and multi-bunch structures. In the future, this type of pulse generator will play an important role in accelerators that require complicated and precise beam handling at high repetition rates of kHz or MHz. [ABSTRACT FROM AUTHOR]

We report a non-blocking high-resolution digital delay line based on an asynchronous circuit design. Field-programmable gate array logic primitives were used as a source of delay and optimally arranged using combinatorial optimization. This approach allows for an efficient trade-off of the resolution and a delay range together with a minimized dead time operation. We demonstrate the method by implementing the delay line adjustable from 23 ns up to 1635 ns with a resolution of 10 ps. We present a detailed experimental characterization of the device focusing on thermal instability, timing jitter, and pulse spreading, which represent three main issues of the asynchronous design. We found a linear dependence of the delay on the temperature with the slope of 0.2 ps K−1 per logic primitive. We measured the timing jitter of the delay to be in the range of 7–165 ps, linearly increasing over the dynamic range of the delay. We reduced the effect of pulse spreading by introducing pulse shrinking circuits and reached the overall dead time of 4–22.5 ns within the dynamic range of the delay. The presented non-blocking delay line finds usage in applications where the dead time minimization is crucial, and tens of picoseconds of excess jitter is acceptable, such as in many advanced photonic networks. [ABSTRACT FROM AUTHOR]

This paper presents a high-stability and low-jitter Arbitrary Timing Generator (ATG) design based on the Xilinx Field Programmable Gate Array (FPGA) and its special integrated delay line. In recent years, FPGA-based or application specific integrated circuit-based delay lines have been used to achieve picosecond-level timing resolution. Devices with pure digital delay methods can only acquire triggers at the clock rising edges when triggered externally. Therefore, there is a large time irregularity caused by the uncertainty of the entry time of the trigger, which is difficult to compensate and leads to a large time jitter of outputs. We describe the design of an ATG that includes jitter self-measurement and calibration methods, which is available for both internal and external trigger modes. This structure is completely based on the FPGA's own resources and has the advantages of being simple and flexible. Experimental results show a sub-nanosecond timing resolution of 78 ± 20 ps with a minimum of 120 ps and a time jitter of 160 ± 20 ps in the external trigger mode after compensation. [ABSTRACT FROM AUTHOR]

Characteristics and performance of a time of flight (TOF) spectrometer developed for performing fission mass distribution studies are presented. The spectrometer contains two TOF arms based on multi-wire proportional counters (MWPCs). Each arm has two MWPCs to form a start–stop detection system for TOF measurements. The start detector has an active area of 4 × 4 cm2. The stop detector is a two-dimensional position sensitive MWPC with an active area of 16 × 11 cm2. Salient features of the MWPCs are the use of reduced sub-millimeter wire pitches of 0.635 and 0.317 mm in the electrodes along with the use of gold plated tungsten wires of diameters 10 and 20 µm. A delay line for position electrodes is prepared using chip inductors and capacitors. Ten different configurations of MWPC were investigated for the start detector, which involved the use of three and four electrode geometries, use of different wire pitches, and use of aluminized mylar for timing electrodes. Performance results close to micro-channel plate detectors have been observed with some designs of MWPC, displaying rise times better than 2 ns with an estimated inherent time resolution of ∼100 ps FWHM. A position resolution of ∼1 mm (FWHM) has been observed. Design features of the MWPCs and their test performance results are described in this article. [ABSTRACT FROM AUTHOR]

The second-order photon correlation function g 2 (τ) is of great importance in quantum optics. g 2 (τ) is typically measured with the Hanbury Brown and Twiss (HBT) interferometer, which employs a pair of single-photon detectors and a dual-channel time acquisition module. Here, we demonstrate a new method to measure and extract g 2 (τ) with a standard single-photon avalanche photodiode (dead-time = 22 ns) and a single-channel time acquisition module. This is realized by shifting the coincidence counts of interest to a time window not affected by the dead-time and after-pulse of the detection system using a fiber-based delay line. The new scheme is verified by measuring g 2 (τ) from a single colloidal nanocrystal. Photon antibunching is unambiguously observed and agrees well with the result measured using the standard HBT setup. Our scheme simplifies the higher-order correlation technique and might be favored in cost-sensitive circumstances. [ABSTRACT FROM AUTHOR]

We report the construction and characterization of a comprehensive magnonic-opto-electronic oscillator (MOEO) system based on 1550-nm photonics and yttrium iron garnet (YIG) magnonics. The system exhibits a rich and synergistic parameter space because of the ability to control individual photonic, electronic, and magnonic components. Taking advantage of the spin wave dispersion of YIG, the frequency self-generation as well as the related nonlinear processes becomes sensitive to the external magnetic field. Besides being known as a band-pass filter and a delay element, the YIG delay line possesses spin wave modes that can be controlled to mix with the optoelectronic modes to generate higher-order harmonic beating modes. With the high sensitivity and external tunability, the MOEO system may find usefulness in sensing applications in magnetism and spintronics beyond optoelectronics and photonics. [ABSTRACT FROM AUTHOR]

We propose a method to generate stabilized radio-frequency polarization modulation based on optical frequency combs. Two pulse trains with the same repetition rate and different offset frequencies generate arbitrary polarization states that are modulated at the offset frequency difference. Long-term stability of the polarization modulation is demonstrated with the modulation frequency at frep/2. Modulation at frep/4 is also demonstrated to show the flexibility of the technique. We employ an electrical delay line to fine-tune the polarization states that constitute the time-dependent modulation. [ABSTRACT FROM AUTHOR]

We present a simple scheme that enables us to automatically relock optical phase locking. Our servo system consists of an analog loop filter for the fast feedback control of a high-speed controllable actuator and a digital circuit for the slow control of another actuator with a broad dynamic range. The digital circuit detects an out-of-lock status and relocks the phase locking using a signal generated by an electrical delay line. We demonstrate to relock the phase locking of a fiber-based frequency comb to a Nd:YAG laser at 1064 nm and that of an external cavity diode laser at 1156 nm to the fiber comb. The relocking scheme is attractive for various applications that employ phase locking and is especially useful for the unattended operation of optical clocks. [ABSTRACT FROM AUTHOR]

An all-digital CMOS (Complementary Metal-Oxide Semiconductor) pulse-shrinking smart temperature sensor (PSSTS) is proposed to deliver the merits of area efficiency, improved accuracy, and high resolution. First, an inverter-based temperature-sensing delay line generates a pulse with a width proportional to absolute temperature (PTAT). Then, a pulse-shrinking delay line (PSDL) with a pulse-mixing scheme (PMS) measures the PTAT pulse through pulse shrinking. The two delay lines become area efficient when the channel length of transistors is long. Conventionally, the area-efficient PSDL decreases the time resolution. Thus, the all-digital PMS considerably enhances the time resolution and achieves an excellent sensor resolution. Finally, a time subtractor improves sensor accuracy by effectively eliminating the offset error effects. The proposed sensor was implemented in a Taiwan Semiconductor Manufacturing Company 0.35-μm CMOS process and occupied an area of 0.0247 mm2, which is the best area among related studies. The PSSTS exhibited an improved inaccuracy from a maximal inaccuracy of 1.95 °C to 1.5 °C and an excellent resolution of approximately 0.05 °C/LSB. Experimental results prove that this study is area-efficient and achieves improved accuracy and high resolution. [ABSTRACT FROM AUTHOR]

The detection efficiency η of any particle detector is important, concerning acquisition time, but becomes even more critical when two particles are detected in coincidence, with a total efficiency η1η2, in order to allow a deeper understanding of complex processes induced by light or particle interaction with matter. Efficiency and resolution of a time and position sensitive x-ray detector are reported here. This system consists of a multilayer transmission photocathode and two micro-channel plates (MCPs) equipped with a delay line anode (DLA). The efficiency is found to be about 20% for Al Kα photons, while the spatial resolution is comparable to that of a standard DLA detector (about 100 μm). The fast response time of the detector combined with its efficiency should allow coincidence experiments between x-ray photons and other particles (electron, ions, etc.). [ABSTRACT FROM AUTHOR]

The method commonly used to produce a field-programmable gate array (FPGA)-based time-to-digital converter (TDC) creates a tapped delay line (TDL) for time interpolation to yield high time precision. We conduct timing adjustment and bin realignment to implement a TDC in the Altera Cyclone-IV FPGA. The former tunes the carry look-up table (LUT) cell delay by changing the LUT’s function through low-level primitives according to timing analysis results, while the latter realigns bins according to the timing result obtained by timing adjustment so as to create a uniform TDL with bins of equivalent width. The differential nonlinearity and time resolution can be improved by realigning the bins. After calibration, the TDC has a 18 ps root-mean-square timing resolution and a 45 ps least-significant bit resolution. [ABSTRACT FROM AUTHOR]

A novel Radio-Frequency Frequency-Modulated (RF-FM) signal generation method is introduced and a prototype circuit developed to evaluate its functionality and performance. The RF-FM signal generator uses a modulated, voltage-controlled time delay to correspondingly modulate the phase of a 10 MHz sinusoidal reference signal. This modulated reference signal is, in turn, used to clock a Direct Digital Synthesizer (DDS) circuit resulting in an FM signal at its output. The modulating signal that is input to the voltage-controlled time delay circuit is generated by another DDS that is synchronously clocked by the same 10 MHz sine wave signal before modulation. As a consequence, all of the digital components are timed from a single sine wave oscillator that forms the basis of all timing. The resultant output signal comprises a center, or carrier, frequency plus a series of phase-synchronized sidebands having exact integer harmonic frequency separation. In this study, carrier frequencies ranging from 10 MHz to 70 MHz are generated with modulation frequencies ranging from 10 kHz to 300 kHz. The captured spectra show that the FM signal characteristics, amplitude and phase, of the sidebands and the modulation depth are consistent with the Jacobi-Anger expansion for modulated harmonic signals. [ABSTRACT FROM AUTHOR]

This paper presents a new all-digital CMOS digital-to-time converter (DTC) based on pulse expansion. Pulse expansion is achieved using an all-digital pulse-mixing scheme that can effectively improve the timing resolution and enable the DTC to be concise. Without requiring the Vernier principle or a costly digital-to-analog converter, the DTC comprises a pulse generator for generating a pulse, a pulse expanding circuit (PEC) for programming timing generation, and a time subtractor for removing the time width of the pulse. The PEC comprises only a delay chain composed of proposed pulse-expanding units and a multiplexer. For accuracy enhancement, a pulse neutralization technique is presented to eliminate undesirable pulse variation. A 4-bit converter was fabricated in a 0.35-μm Taiwan Semiconductor Manufacturing Company CMOS process and had a small area of nearly 0.045 mm2. Six chips were tested, all of which exhibited an improved resolution (approximately 16 ps) and low integral nonlinearity (less than ±0.4 least significant bit). The power consumption was 0.2 mW when the sample rate was 1M samples/s and the voltage supply was 3.3 V. The proposed DTC not only has favorable cost and power but also achieves an acceptable resolution without requiring an advanced CMOS process. This study is the first to use pulse expansion in digital-to-time conversion. [ABSTRACT FROM AUTHOR]

We have developed a femtosecond single-shot spectroscopic technique to measure irreversible changes in condensed phase materials in real time. Crossed echelons generate a two-dimensional array of time-delayed pulses with one femtosecond probe pulse. This yields 9 ps of time-resolved data from a single laser shot, filling a gap in currently employed measurement methods. We can now monitor ultrafast irreversible dynamics in solid-state materials or other samples that cannot be flowed or replenished between laser shots, circumventing limitations of conventional pump-probe methods due to sample damage or product buildup. Despite the absence of signal-averaging in the single-shot measurement, an acceptable signal-to-noise level has been achieved via background and reference calibration procedures. Pump-induced changes in relative reflectivity as small as 0.2%-0.5% are demonstrated in semimetals, with both electronic and coherent phonon dynamics revealed by the data. The optical arrangement and the space-to-time conversion and calibration procedures necessary to achieve this level of operation are described. Sources of noise and approaches for dealing with them are discussed. [ABSTRACT FROM AUTHOR]

We have developed a rotatable hemispherical spectrometer with good energy and angular resolution, which can be positioned with the lens axis arbitrarily within a solid angle of 1 π. The collection angle of the emitted electrons with respect to the polarization axis of the light is set by means of a three-axes goniometer, operating under vacuum. An important requirement for this setup was the possibility to perform coincidences between the electron analyzed by the spectrometer and one or several other particles, such as ions, electrons, or photons. The lens system and the hemispheres have been designed to accommodate such experimental demands, regarding parameters such as the resolving power, the acceptance angle, or the width of the kinetic energy window which can be recorded for a given pass energy. We have chosen to detect the impact position of the electron at the focal plane of the hemispherical analyzer with a delay line detector and a time-to-digital converter as acquisition card rather than using a conventional charge-coupled device camera. [ABSTRACT FROM AUTHOR]

Free space delay lines provide pulses of variable time spacing for optical experiments such as pump-probe spectroscopy and coherent quantum control, including spin and photon echo techniques. However, in the terahertz region of the spectrum, beam divergence due to diffraction limits the useful length of traditional free space delay lines. We present a novel double-folded variable delay line for light in the frequency range 0.24–1.2 THz, which incorporates a symmetric arrangement of lenses whose spacing can be adjusted to compensate for diffraction at each delay. Scalable for use in other wavelength regimes, the design relays an input Gaussian beam waist to the output with up to 25 ns (∼8 m) total delay and is enclosed in a desiccated volume of <0.5 m3. The delay line can deliver two or three pulses with relative amplitudes controlled via variable spacing silicon étalon beam splitters. Profiles of a 0.24 THz beam show good agreement with calculations at long delays, with insertion loss per delay stage of ∼3 dB. [ABSTRACT FROM AUTHOR]

We describe a circuit that acts as an auto-incrementing delay. The circuit allows the user to adjust the total number of delays in a cycle, the incremental delay value, and the amount of time that is spent at each delay step. The circuit is stand-alone, yet is readily interfaced to data acquisition systems. Depending on the delay chip used and the number of steps required, the delay step can be as short as 250 ps or as long as 640 ns. The circuit has been used to control the temporal separation between pulses from independent lasers. This was instrumental in our measurement of population dynamics in an optically excited three-level ladder system. [ABSTRACT FROM AUTHOR]

We have combined a commercially available, variable-length coaxial delay line (trombone line) with a high-resolution linear translation system. The result is better resolution and lower uncertainty in the achievable delays than previously available. The range of delay is 0 ps to approximately 1250 ps, the bidirectional resolution is 2.0 ps, the unidirectional resolution is 0.2 ps, and the uncertainty (95% confidence interval) in the measured delay is ±0.09 ps. Drift, temperature dependence, repeatability, linearity, and hysteresis were also examined. [ABSTRACT FROM AUTHOR]

We describe a fast measurement of a pulsed terahertz signal generated by a femtosecond laser and a photoconductive antenna using an oscillating optical delay line. The method to measure the amplitude of the retroreflector in the oscillating optical delay line is proposed and the displacement of the retroreflector is exactly calculated to acquire the optical delay time in the fast scan mode. With the different oscillation frequency and amplitude of the retroreflector, the pulsed terahertz signals are measured and analyzed. The comparison of the temporal waveform and frequency spectrum between the fast scan mode and the slow scan mode shows a good agreement with the decrease in the scanning time from 60 to 1 s at a signal to noise ratio of 430. [ABSTRACT FROM AUTHOR]

A low energy electron diffraction (LEED) instrument incorporating a delay line detector has been constructed to rapidly collect high-quality digital LEED images with low total electron exposures. The system uses a position-sensitive pulse-counting detector with high bias current microchannel plates. This delay-line detector combined with a femtoampere electron gun offers a wide range of flexibility, with electron dosing currents ranging from 0.15 pA to 0.3 fA. Using the highest current setting and collecting 1×106 counts per image, individual LEED images can be completed in 4 s with an acquisition rate of 250 kHz and a total electron exposure of 5×106 electrons. Under the latter conditions, images can be collected in 20 min with an acquisition rate of 1 kHz with a total electron exposure of 2×106 electrons. An angular width of 0.13° at 108 eV is demonstrated, which means that domain sizes as large as 600 Å can be resolved, depending on the surface quality of the crystal. The system electronics collect 2048×2048 pixel images with a spatial resolution of about 75 μm. The dynamic range of this system is 32 bits/pixel (limited only by physical memory). The construction of the detector results in a “plus”-shaped artifact, which requires that, for a given sample orientation, two images be taken at a relative angle of 45°. Identical current-voltage curves from an MgO(111)1×1 H terminated sample, taken during several hours of exposure to the low current electron beam, demonstrate minimal electron induced H desorption. [ABSTRACT FROM AUTHOR]

Time-delay anodes are typically used in conjunction with microchannel plates to create photon counting, two-dimensional imaging detectors. The anode and associated electronics are used to compute the centroid of the charge cloud from the microchannel plate stack. The computation of event position is done in analog circuitry and then digitized to an appropriate number of bits. The analog nature of the time-delay anode makes it susceptible to a wide variety of outside influences resulting in variations in the correlation between physical space and the reported digital value. These variations, both local and global, must be corrected as part of the reduction of scientific data. If left uncorrected in spectral data, for example, these variations result in decreased spectral resolution, inaccurate wavelength identifications, and/or distorted spectral line profiles. This work presents successful algorithms for correcting the dominant distortions present in a time-delay anode. These algorithms were developed as part of the data reduction pipeline for the cosmic origins spectrograph (COS) far ultraviolet channel. COS is a fourth generation instrument for the Hubble Space Telescope. [ABSTRACT FROM AUTHOR]

Examines the development of optical oscilloscope based on the image-converter tube camera technology. Adoption of optical-fiber delay unit to detect optical and electrical pulses; Sensitivity and temporal resolution of the optical oscilloscope; Components of the device.

Proposes a method of surface impedance measurement for small samples. Use of an yttrium iron garnet delay line in measuring surface impedance; Calculation of the dispersion relations of the magnetostatic wave; Analysis of the measurement sensitivity; Effect of temperature on the surface impedance of the sample.

Describes the design, construction, and testing of an imaging microchannel plate detector that uses two crossed, printed circuit, serpentine delay lines, one stacked above the other in a three-dimensional architecture. Theory of operation; Electronics; Transmission line measurements and the microstrip approximation; Spatial linearity.

A new dual channel time digitizer has been designed. It is based on the coarse counter and interpolation method. A new technique of interpolation has been employed which gives a FWHM resolution of 50 ps and a differential nonlinearity of ±2%, at a master oscillator frequency of 200 MHz. The module has a dynamic measurement range of 10 bits with a fixed dead time of 30 ns. It is a single width C size VXI format. Presented is a description of the new interpolation method and typical performance results. [ABSTRACT FROM AUTHOR]

We describe a photon-counting readout system for microchannel-plate spectrometers that uses a delay line and timing circuit for the wavelength coordinate and a wedge–wedge charge division system for the orthogonal spatial coordinate. A novel zigzag layout allows these two anode patterns to coexist on a common planar substrate and share the charge from each photoevent, thereby simultaneously localizing the photon in each of its two dimensions. Unlike wedge-and-strip or resistive anode encoders, the delay line offers a spatial resolution that is relatively independent of the format length. Unlike discrete anode systems, the delay line readout system’s complexity is also independent of the field of view size. These facts make the delay line readout system advantageous in large format detectors. We have assembled a testbed detector having a delay line propagation speed of 2.2 mm/ns and a time resolution of 33 ps FWHM. Ultraviolet testing shows a Gaussian event distribution having a 70 μm FWHM width; the readout system blur contribution is less than 50 μm FWHM. [ABSTRACT FROM AUTHOR]

In broadband microwave reflectometry, coherent detection is widely used to obtain the phase information and to improve the systems sensitivity, both in diagnostics measuring the electronic density profile and plasma fluctuations. Coherent detection uses a translated version of the probing signal to guarantee a stable intermediate frequency. Here, a novel technique to generate the frequency translation by double frequency conversion is presented and its advantages over the commonly used single frequency conversion techniques employing image rejection mixers are discussed. The results obtained with the new frequency translator modules developed for the three JET FM-CW reflectometers, operating successfully at JET since mid-2009, are presented. [ABSTRACT FROM AUTHOR]

We demonstrate high speed scanning of a time-domain terahertz pulse by a rotary optical delay line (RODL) incorporated into a photoconductive antenna based terahertz system. The delay line of RODL consists of six rotating convex reflective blades with a rotating speed controlled for a wide range of scan repetition rates. It can perform path length scans of 2.1 cm at a scanning speed of 8.4 m/s while maintaining linearity. The comparison of the terahertz temporal waveform and the frequency spectrum measured by using the RODL and a linear stage optical delay line confirms the linearity of the RODL up to 140 ps at high scan repetition rates of 400 scan/s. A high signal-to-noise ratio, up to a few thousand, can be obtained by averaging multiple terahertz pulses at a high scan speed. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a newly designed optical delay line (W-type delay line) that improves the resolution of optical path length, namely, time resolution, by an order of more than 3 in comparison to the spatial resolution of a conventionally used translational stage. Using a conventional mechanical translational stage having a spatial resolution of 1 μm, the performance of the W-type delay line was evaluated by interferometric measurements with a diode laser, and the time resolution of 16 as was confirmed. [ABSTRACT FROM AUTHOR]

Describes how a fast main amplifier for x-ray measurements was developed through the modification of a commercially available delay-line amplifier. Evaluation of the characteristics of the modified amplifier; Output pulse width.

A versatile digital delay generator is described which is built using the widely available C64 Commodore home computer. Fixed delays and delay scans from 1 μs up to 65 ms with 1-μs step size are possible. One can modify the generator program; for instance, a delay scan followed by a number of fixed delay sequences. The speed of a delay scan is adjustable over a very wide range and the accuracy of the delay generation depends uniquely on the system clock accuracy. [ABSTRACT FROM AUTHOR]

An inexpensive high-speed multichannel digitizing system was constructed based on Reticon analog delay lines. In the present configuration the system was capable of recording 512 successive samples at a 1.6-MHz sampling rate for each of 64 separate channels. [ABSTRACT FROM AUTHOR]

The Cosmic Hot Interstellar Plasma Spectrometer (CHIPS) utilizes a typical microchannel plate detector with a cross delay line event readout anode. A CHIPS delay line was predicted to approach a time delay of 80 ns. Therefore an added time delay of 100 ns was required for the stop channels. Implementation of such a delay using conventional coax cable was deemed too bulky and massive. After exploring other alternatives, which failed to meet specific requirements, a stripline delay printed circuit board was developed. This approach eventually proved to be a superior alternative to coax cable for the CHIPS detector. This article outlines and details the development of the CHIPS external stop delay board from basic microwave circuit theory to design and testing. Discussion of the mathematical and computer models used for design are contained in the Appendices. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We demonstrate a multilayer circuit board that has two orthogonal serpentine delay lines on different layers to read out event positions from a microchannel plate (MCP). The top serpentine is directly bombarded by the MCP. The orthogonal buried serpentine receives its charge through thousands of vias that connect to the top surface. Event X and Y positions are decoded with a timing circuit for each axis. The spatial resolution is much finer than the via spacing because every event's charge footprint spans several vias, and because the timing circuit senses the centroid of the event's position on each delay line. This construction method eliminates fabrication problems encountered in previous multilayer designs and eliminates the need for crossed conducting fingers with their concomitant degradation of the otherwise excellent phase delay characteristic of serpentine delay lines. Performance data are presented for an anode of this new type. Formulas and graphs are given to assist in creating a variety of anodes of this type. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]