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1.
J Synchrotron Radiat ; 31(Pt 4): 670-680, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38838166

ABSTRACT

Deflectometric profilometers are used to precisely measure the form of beam shaping optics of synchrotrons and X-ray free-electron lasers. They often utilize autocollimators which measure slope by evaluating the displacement of a reticle image on a detector. Based on our privileged access to the raw image data of an autocollimator, novel strategies to reduce the systematic measurement errors by using a set of overlapping images of the reticle obtained at different positions on the detector are discussed. It is demonstrated that imaging properties such as, for example, geometrical distortions and vignetting, can be extracted from this redundant set of images without recourse to external calibration facilities. This approach is based on the fact that the properties of the reticle itself do not change - all changes in the reticle image are due to the imaging process. Firstly, by combining interpolation and correlation, it is possible to determine the shift of a reticle image relative to a reference image with minimal error propagation. Secondly, the intensity of the reticle image is analysed as a function of its position on the CCD and a vignetting correction is calculated. Thirdly, the size of the reticle image is analysed as a function of its position and an imaging distortion correction is derived. It is demonstrated that, for different measurement ranges and aperture diameters of the autocollimator, reductions in the systematic errors of up to a factor of four to five can be achieved without recourse to external measurements.

2.
J Synchrotron Radiat ; 28(Pt 4): 1031-1040, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34212866

ABSTRACT

A new type of optical element that can focus a cylindrical wave to a point focus (or vice versa) is analytically described. Such waves are, for example, produced in a beamline where light is collimated in one direction and then doubly focused by a single optic. A classical example in X-ray optics is the collimated two-crystal monochromator, with toroidal mirror refocusing. The element here replaces the toroid, and in such a system provides completely aberration free, point-to-point imaging of rays from the on-axis source point. We present an analytic solution for the mirror shape in its laboratory coordinate system with zero slope at the centre, and approximate solutions, based on bending an oblique circular cone and a bent right circular cylinder, that may facilitate fabrication and metrology.

3.
J Synchrotron Radiat ; 28(Pt 4): 1041-1049, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-34212867

ABSTRACT

The diaboloid is a reflecting surface that converts a spherical wave to a cylindrical wave. This complex surface may find application in new Advanced Light Source bending-magnet beamlines or in other beamlines that now use toroidal optics for astigmatic focusing. Here, the numerical implementation of diaboloid mirrors is described, and the benefit of this mirror in beamlines exploiting diffraction-limited storage rings is studied by ray tracing. The use of diaboloids becomes especially interesting for the new low-emittance storage rings because the reduction of aberration becomes essential for such small sources. The validity of the toroidal and other mirror surfaces approximating the diaboloid, and the effect of the mirror magnification, are discussed.

4.
Rev Sci Instrum ; 91(7): 075113, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32752867

ABSTRACT

We present experimental, analytical, and numerical methods developed for reconstruction (deconvolution) of one-dimensional (1D) surface slope profiles over the spatial frequency range where the raw data are significantly perturbed due to the limited resolution of the measurement instrument. We characterize the spatial resolution properties of a profiler with the instrument's transfer function (ITF). To precisely measure the ITF, we apply a recently developed method utilizing test surfaces with 1D linear chirped height profiles of constant slope amplitude. Based on the results of the ITF calibration, we determine parameters of an analytical model for the ITF that is used in the original reconstruction software. Here, we treat surface slope metrology data obtained with the Optical Surface Measuring System (OSMS), using as a sensor an electronic autocollimator (AC) ELCOMAT-3000. The spatial resolution of the OSMS is limited by the size of the AC light-beam-collimating aperture. For the purposes of this investigation, the OSMS is equipped with a circular aperture with a diameter of 2.5 mm. This is a typical arrangement of most AC-based slope profilers developed for surface slope metrology of state-of-the-art x-ray mirrors. Using the example of surface slope metrology of two state-of-the-art elliptically shaped x-ray focusing mirrors, we demonstrate that the developed data reconstruction procedure allows us to significantly improve the accuracy of surface slope metrology with the OSMS over the spatial wavelength range from ∼1.6 mm to 7 mm. Thus, the amplitude of the quasi-periodic error characteristic of the deterministic polishing process used appears to be higher by a factor of ∼2 than is apparent from the rough metrology data. Underestimation of the surface slope errors in this spatial wavelength range can lead to serious errors in the expected performance of x-ray mirrors in synchrotron beamlines, especially at modern light sources utilizing coherent x rays, where the perturbations can lead to increased speckle-like intensity variation.

5.
Rev Sci Instrum ; 90(2): 021717, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30831748

ABSTRACT

Deflectometric profilometers based on industrial electronic autocollimators (ACs), as the ELCOMAT-3000, have become indispensable tools for precision form measurements of optical surfaces. A growing number of labs at synchrotron and free electron laser x-ray facilities are going for BESSY-II NOM-like versions of the AC-based profilometers. These tools have proven capable of characterizing state-of-the-art aspherical x-ray optics with an accuracy on the level of 100 nrad (root-mean-square) over the spatial frequency range limited by the size of the aperture used in the profilometer. Typically, a round aperture with a diameter of about 2.5 mm is used. Previous investigations have shown that with the optimally aligned 2.5-mm aperture, the spatial resolution of a NOM-like profilometer corresponding to the first zero-crossing of the optical transform function (OTF) is ∼1.2 mm. In this paper, we investigate the performance of an AC ELCOMAT-3000 for a slope profilometer with different aperture sizes and shapes. The results of angular calibration of the AC equipped with circular and rectangular apertures placed at different distances from the AC are discussed. The calibration was performed at the Physikalisch-Technische Bundesanstalt using the original experimental arrangements, also discussed in the paper. The OTF measurements with the specially developed test sample with chirped surface slope profiles were performed at the Advanced Light Source X-Ray Optics Laboratory (XROL) in application to a new optical surface measuring system under development at the XROL. In the OTF measurements, we have shown that application of a rectangular aperture with dimensions of 1.5 mm × 3 mm improves the spatial resolution in the tangential direction by a factor of ∼1.4 compared to that of the standard circular aperture of 2.5-mm diameter. We believe that the results of our investigations are crucial for reaching fundamental metrological limits in deflectometric profilometry utilizing state-of-the-art electronic autocollimators.

6.
Rev Sci Instrum ; 90(2): 021705, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30831764

ABSTRACT

Deflectometric profilometers are indispensable tools for the precision form measurement of beam-shaping optics of synchrotrons and x-ray free electron lasers. They are used in metrology labs for x-ray optics worldwide and are crucial for providing measurement accuracy dictated by the form tolerances for modern state-of-the-art x-ray optics. Deflectometric profilometers use surface slope (angle) to assess form, and they utilize commercial autocollimators for the contactless slope measurement. In this contribution, we discuss the influences of environmental parameters, such as temperature and air pressure, including their gradients, on high-accuracy metrology with autocollimators in profilometers. They can cause substantial systematic errors in form measurement, especially in the case of large and strongly curved optical surfaces of high dynamic range. Relative angle and form measuring errors of the order of 10-4 are to be expected. We characterize environmental influences by extended theoretical and experimental investigations and derive strategies for correcting them. We also discuss the possibility to minimize the contributions of some errors by the application of sophisticated experimental arrangements and methods. This work aims at approaching fundamental limits in autocollimator-based slope and form metrology.

7.
Rev Sci Instrum ; 90(2): 021711, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30831770

ABSTRACT

Super high quality aspherical x-ray mirrors with a residual slope error of ∼100 nrad (root-mean-square) and a height error of ∼1-2 nm (peak-to-valley), and even lower, are now available from a number of the most advanced vendors utilizing deterministic polishing techniques. The mirror specification for the fabrication is based on the simulations of the desired performance of the mirror in the beamline optical system and is normally given with the acceptable level of deviation of the mirror figure and finish from the desired ideal shape. For example, in the case of aspherical x-ray mirrors designed for the Advanced Light Source (ALS) QERLIN beamline, the ideal shape is defined with the beamline application (conjugate) parameters and their tolerances. In this paper, we first discuss an original procedure and dedicated software developed at the ALS X-Ray Optics Laboratory (XROL) for optimization of beamline performance of pre-shaped hyperbolic and elliptical mirrors. The optimization is based on results of ex situ surface slope metrology and consists in minimization of the mirror shape error by determining the conjugate parameters of the best-fit ideal shape within the specified tolerances. We describe novel optical metrology instrumentation, measuring techniques, and analytical methods used at the XROL for acquisition of surface slope data and optimization of the optic's beamline performance. The high efficacy of the developed experimental methods and data analysis procedures is demonstrated in results of measurements with and performance optimization of hyperbolic and elliptical cylinder mirrors designed and fabricated for the ALS QERLIN beamline.

8.
Rev Sci Instrum ; 87(5): 051904, 2016 05.
Article in English | MEDLINE | ID: mdl-27250376

ABSTRACT

The ultimate performance of surface slope metrology instrumentation, such as long trace profilers and auto-collimator based deflectometers, is limited by systematic errors that are increased when the entire angular range is used for metrology of significantly curved optics. At the ALS X-Ray Optics Laboratory, in collaboration with the HZB/BESSY-II and PTB (Germany) metrology teams, we are working on a calibration method for deflectometers, based on a concept of a universal test mirror (UTM) [V. V. Yashchuk et al., Proc. SPIE 6704, 67040A (2007)]. Potentially, the UTM method provides high performance calibration and accounts for peculiarities of the optics under test (e.g., slope distribution) and the experimental arrangement (e.g., the distance between the sensor and the optic under test). At the same time, the UTM calibration method is inherently universal, applicable to a variety of optics and experimental arrangements. In this work, we present the results of tests with a key component of the UTM system, a custom high precision tilt stage, which has been recently developed in collaboration with Physik Instrumente, GmbH. The tests have demonstrated high performance of the stage and its capability (after additional calibration) to provide angular calibration of surface slope measuring profilers over the entire instrumental dynamic range with absolute accuracy better than 30 nrad. The details of the stage design and tests are presented. We also discuss the foundation of the UTM method and calibration algorithm, as well as the possible design of a full scale UTM system.

9.
J Econ Entomol ; 108(4): 1930-5, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26470337

ABSTRACT

Eradication technologies are needed for urban and suburban situations, but may require different technologies from pest management in agriculture. We investigated mating disruption of a model moth species recently targeted for eradication in Californian cities, by applying dollops of SPLAT releasing a two-component sex pheromone of the light brown apple moth in 2-ha plots in low-density residential Perth, Australia. The pheromone technology was applied manually at ∼1.5 m height to street and garden trees, scrubs, and walls at 500 dollops per hectare of 0.8 g containing ∼80 mg active two-component pheromone. Catches of male moths were similar among all plots before treatment, but in treated areas (six replicates) pheromone trap catches were substantially reduced for up to 29 wk posttreatment, compared with untreated control plot catches (three replicates). The treatment with pheromone reduced catch to virgin females by 86% (P < 0.001) and reduced the occurrence of mating by 93%, compared with three equivalent untreated control plot catches (P < 0.001). Eradication programs are following an upward trend with globalization and the spread of invasive arthropods, which are often first detected in urban areas. Eradication requires a major increase in the communication distance between individuals, but this can be achieved using sex pheromone-based mating disruption technology, which is very benign and suitable for sensitive environments. The need for new socially acceptable tools for eradication in urban environments is likely to increase because of increasing need for eradications.


Subject(s)
Moths/drug effects , Pest Control, Biological , Pheromones/pharmacology , Sex Attractants/pharmacology , Sexual Behavior, Animal/drug effects , Animals , Female , Male , Western Australia
10.
Aust J Prim Health ; 20(4): 379-83, 2014.
Article in English | MEDLINE | ID: mdl-25262748

ABSTRACT

The present study was an evaluation of the effectiveness of Deadly Choices™ community events for improving participants' short-term knowledge of chronic disease and risk factors, and increasing community engagement with local health services. Surveys were completed directly before and after participating in health education activities (pre and post surveys, respectively) assessing knowledge of chronic diseases and risk factors at three Deadly Choices community events and four National Aboriginal and Islander Day Observance Committee (NAIDOC) events in south-east Queensland where Deadly Choices health education activities took place. An audit trail was conducted at two Deadly Choices community events in Brisbane to identify the proportion of participants who undertook a health screen at the event who then followed up for a Medicare-funded health check (MBS item 715) or other appointment at an Aboriginal and Torres Strait Islander clinic in the local area within 2 months. Results were compared with a sample of participants who attended one Deadly Choices community event but did not complete a health screen. There were 472 community members who completed a pre and post survey. All knowledge scores significantly improved between baseline and follow up. Although based on a small sample, the audit trail results suggest individuals who participated in a health screen at the community day were approximately twice as likely to go back to a clinic to receive a full health check or have an alternative appointment compared with attendees who did not participate in a screen. Community events that include opportunities for health education and health screening are an effective strategy to improve chronic disease health literacy skills and appear to have the potential to increase community engagement with local Aboriginal and Torres Strait Islander health services.


Subject(s)
Community Health Services/methods , Health Knowledge, Attitudes, Practice , Health Promotion/methods , Health Services, Indigenous/statistics & numerical data , Native Hawaiian or Other Pacific Islander/statistics & numerical data , Program Evaluation/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Child , Chronic Disease , Community Health Services/statistics & numerical data , Community-Based Participatory Research/methods , Community-Based Participatory Research/statistics & numerical data , Female , Follow-Up Studies , Health Education/methods , Health Education/statistics & numerical data , Health Promotion/statistics & numerical data , Humans , Male , Middle Aged , Program Evaluation/methods , Queensland , Risk Factors , Urban Population/statistics & numerical data , Young Adult
11.
Pest Manag Sci ; 67(8): 1004-14, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21480460

ABSTRACT

BACKGROUND: Public opposition to aerial application of sex pheromone for mating disruption of light-brown apple moth (LBAM), Epiphyas postvittana (Walk.), in California stopped its further use in the ca $74 million eradication programme in 2008, underscoring the need for other eradication tactics. It is demonstrated that pheromone-treated sterile Mediterranean fruit flies (medflies), Ceratitis capitata Wied., can disrupt communication in male moths. RESULTS: Medflies topically dosed with moth pheromone (E)-11-tetradecenyl acetate showed a no observed effect level (NOEL) of ~10 µg fly(-1) , with increasing toxicity from 30 to 100 µg fly(-1) . Greater potency and longevity of attraction and lower mortality were achieved using microencapsulated pheromone. Releases of 1000 pheromone-treated medflies ha(-1) prevented male moth catch to synthetic lures in treated 4 ha plots for 1 day in suburban Perth, Australia. Releases of ca 3000 pheromone-treated medflies ha(-1) disrupted catch to single female moths in delta traps, and to synthetic pheromone lures. Percentage disruption on the first four nights was 95, 91, 82 and 85%. CONCLUSIONS: Disruption of moth catch using pheromone-treated medflies is a novel development that, with future improvement, might provide a socially acceptable approach for application of the insect mating disruption technique to control invasive insects in urban environments. Adequacy of payload and other issues require resolution.


Subject(s)
Ceratitis capitata , Fatty Acids, Monounsaturated/administration & dosage , Moths , Pest Control, Biological/methods , Sex Attractants/administration & dosage , Animals , Fatty Acids, Monounsaturated/standards , Female , Male , No-Observed-Adverse-Effect Level , Sex Attractants/standards
12.
J Econ Entomol ; 104(6): 1999-2008, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22299363

ABSTRACT

The radiation biology of two geographically isolated populations of the light brown apple moth [Epiphyas postvittana (Walker)] was studied in Australia and New Zealand as an initiation of a SIT/F1 sterility program. Pharate and < or = 2 d pre-emergence pupae were exposed to increasing radiation doses up to a maximum dose of 300 Gy. Fertility and other life history parameters were measured in emerging adults (parental) and their progeny (F1-F3 adults). Parental fecundity was significantly affected by increasing irradiation dose in pharate pupae only. For both populations, parental egg fertility declined with increasing radiation. This was most pronounced for the irradiated parental females whose fertility declined at a higher rate than of irradiated males. At 250 Gy, females < or = 2 d preemergence pupae produced few larvae and no adults at F1. No larvae hatched from 250 Gy-irradiated female pharate pupae. At 300 Gy, males still had residual fertility of 2-5.5%, with pharate pupae being the more radio-sensitive. Radiation-induced deleterious inherited effects in offspring from irradiated males were expressed as increased developmental time in F1 larvae, a reduction in percent F1 female survival, decreased adult emergence and increased cumulative mortality over subsequent generations. Males irradiated at > or = 150 Gy produced few but highly sterile offspring at F1 and mortality was > 99% by F2 egg.


Subject(s)
Gamma Rays , Moths/radiation effects , Pest Control, Biological/methods , Animals , Dose-Response Relationship, Radiation , Female , Fertility , Male , Mortality , New Zealand , Pupa/radiation effects , Reproduction , Western Australia
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