X-ray focusing using microchannel plates

Kaaret, Philip; Geissbühler, P.; Chen, Andrew; Glavinas, E.

doi:10.1364/ao.31.007339

Cited by 46 publications

(24 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…AFM images obtained with the Philips type P1 sample clearly showed striations -linear features parallel to the long axis of the channel, previously noted by Kaaret et al [9] . It is interesting to note that the square core bar used in the manufacture of the Philips boule was ground down from a circularly symmetric original and was not optically polished before fibre was drawn.…”

Section: Metrologysupporting

confidence: 75%

“…Talystep) because of the small size of the reflecting surfaces. Kaaret et al [9] have used an optical profilometer to obtain surface roughness measurements on a first generation [5] hydrogen-reduced Galileo square-pore MCP . We have prepared diamond-sawn slices of all the plate types listed in Table 1 for investigation in an AFM equipped with a cusp-shaped tip.…”

Section: Metrologymentioning

confidence: 99%

See 1 more Smart Citation

<title>Development of microchannel plate (MCP) x-ray optics</title>

et al. 1994

View full text Add to dashboard Cite

The keys to the realisation of efficient microchannel plate (MCP) optics for X-ray astronomy are (a) the production of MCPs with channels of square cross-section and (b) the development of a technology for "slumping" channel plates to a spherical format. We have recently described substantial progress in both these areas (Fraser et al., Nucl.Instr.Meth. A 324 (1993) 404 and Nucl.Instr.Meth. A, in press (1993)). In the present paper, we describe further X-ray images obtained using planar, square pore MCPs in "point-to-point" focusing mode. Angular resolution of 5 arcminutes fwhm has now been measured for full-field illumination of a hydrogen-reduced Galileo MCP (29 mm active diameter ; 44,000 active channels). Secondly, we report some preliminary metrology of square-pore microchannel plates using atomic force, scanning electron and optical microscopies. Finally, we extend our study of spherically-slumped, round-pore Philips MCPs operated as X-ray "beam expanders" . Output images have now been obtained with pointlike sources of 0.28 -17.5 keY X-rays at the foci of MCP "X-ray lenses" of both 1 mm and 4 mm thickness . The measured X-ray intensity distributions are in good agreement with the predictions of a Monte Carlo ray trace model. k INTRODUCTIONThe X-ray focusing action of lead oxide glass microchannel plates is based on equiangular reflection from the interior channel walls [1]. Channels of square cross-section are to be greatly preferred over conventional round pores for reasons of focusing efficiency [2] . Any planar channel plate will form an image of a point X-ray source at a distance from the MCP equal to the source-MCP separation. If the MCP surface can be "slumped" to follow a sphere of radius R, the resulting optical element is capable of focusing a parallel beam to a point or, conversely, of expanding a l)Oiflt source into a quasi-parallel output beam. For arbitrary curvature R and source distance I (see fig. 1), the focusing action of the microchannel structure is governed by the equationwhere i is the focal distance and R is taken to be positive when the plate is concave as viewed from the source [3]. It is therefore entirely appropriate to speak of microchannel plate "X-ray lenses". Microchannel plate optics are, furthermore, truly image forming, unlike capillary bundles [4], where the multiple-reflection ray paths are wholly determined by the capillary curvature. * Now with Nova Scientific Inc., Sturbridge Ma. 0-8194-1260-0/94/$6.00 SPIE Vol. 2011 / 215 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 07/03/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

show abstract

Section: Metrologysupporting

confidence: 75%

Section: Metrologymentioning

confidence: 99%

<title>Development of microchannel plate (MCP) x-ray optics</title>

et al. 1994

View full text Add to dashboard Cite

show abstract

“…It is a fortunate circumstance of nature that the very sume capillary lenses can be used to focus both x-rays and thermal neutrons (Chen et al 1992; Mildner et al 1993). Staff at the National Institute of Standards and Technology (NIST) have led efforts to demonstrate the utility of neutron focying for numerous applications.…”

Section: Tablesmentioning

confidence: 99%

“…Three studies have put forth values ranging from 3881 to 5781 for the surface roughness of the glass channels within a microchannel plate (MCP). The first of these (Kaaret et al 1992) used optical profilometry and is not associated with any particular correlation length. The second (Fraser et al 1993) usis surface roughness as…”

Section: 11mentioning

confidence: 99%

Capillary optics for radiation focusing

Peurrung¹,

Reeder²,

Bliss³

et al. 1996

View full text Add to dashboard Cite

SummaryCapillary lens technology may ultimately bring benefits to neutron and x-ray-based science commensurate with the benefits provided by conventional lenses that focus visible light. A capillary lens consists of a large number of hollow capillaries, each of which gathers some frzlction of the available incident radiation and guides it so that all of the transmitted radiation is directed for maximum utility. (Often, the outgoing radiation is made to converge at a common focal point.) Although the technology for capillary optics is not yet 10 years old, these lenses have already had a significant impact in a number of areas of engineeringy science, and medicine. In general, capillary lenses provide maximum advantage whenever it is desirable to increase the radiation flux at a specific location without regard to its angular divergence. In the future, more efficient capillary lenses will probably be developed that achieve much higher intensity gains by guiding radiation to a smaller focal point. These anticipated improvements can only widen the range of applications for which capillary lenses are well suited.Pacific Northwest National Laboratory (PNNL) has worked to improve this technology in a number of ways. A neutron-sensitive fiber optic faceplate may greatly shorten the time required for experimental measurements involving capillary neutron lenses. A single, optimally tapered capillary was manufactured at PNNL. This singZe taper allows intensity gains of a factor of 270 to be achieved for an hiti@ parallel, incident x-ray beam. The feasibility of two separate methods that might bk used to construct neutron lenses incorporating 'Wi and thus having improved focusing power has been explored at PNNL. The isotope 5Wi is particularly effective at reflecting neutrons, a critical fator in the construction of neutron lenses. First, it might be possible to use glass rich in this isotope. 'Second, it might be possible to construct capillary lenses constructed entirely fiom metal capillaries. These metal capillaries could then either be composed of or coated with nearly pure 58Ni. Each of these improvements to capillary lens technology is discussed in Section 3.0.In addition to striving for fundamental technological advances, PNNL has identified and investigated three applications for capillary optics. First, a capillary neutron lens should be capable of measurjng the strength of a neutron-emitthg source fiom substantially greater distances than allowed by conventional methods of neutron detection. The device that accomplishes this measurement has been dubbed the "neutron .telescope." Second, a capillary x-ray lens has been acquired and studied for the application of small-particle cliflkactometry. Although current technology cau iden* small crystalline particles through difkxtometry, measurement times can be as long as one week It is hoped that ultimately x-ray lenses will shorten this time by 1-2 orders of magnitude. Finally, an investigation of the use of capillary lenses for neutron radiotherapy of deep-seated tumo...

show abstract

“…7,8 Imaging by use of dihedral corner reflector array has been conventionally used for scanners 9 and X-ray focusing. [10][11][12] A schematic diagram showing the imaging principle is shown in Figure 2. Double reflections perform retro-reflection in the plane parallel to the reflector array.…”

Section: Introductionmentioning

confidence: 99%

Aerial 3D LED display by use of retroreflective sheeting

Yamamoto

Suyama

2013

SPIE Proceedings

View full text Add to dashboard Cite

We propose a new optical configuration to form aerial 3D LEDs by use of retroreflective sheeting. The proposed configuration is composed of LEDs, a half mirror, and retroreflective sheeting. A half of the LED lights are reflected by the half mirror and impinge on the retroreflective sheeting. The retroreflective sheeting reflects the lights back to their sources. On the way to the sources, a half of the lights transmit through the half mirror and form the real images of LEDs. Although less than 25 % of the output lights are contributed to the aerial image, recent LED panels have enough luminance to enjoy the aerial image with a quarter of the luminance. We have made a prototype of the proposed aerial LED display. An aerial image of the LED panel has been successfully formed in free space. Its viewing angle was significantly improved compared to the aerial display by use of crossed mirrors, which limit the viewing angle by aperture size and height of mirror walls. The viewing angle in the proposed configuration is mainly limited by the size of the retroreflective sheeting. Furthermore, by using LEDs in different depths, we realized an aerial 3D display in free space.

show abstract

X-ray focusing using microchannel plates

Cited by 46 publications

References 3 publications

<title>Development of microchannel plate (MCP) x-ray optics</title>

<title>Development of microchannel plate (MCP) x-ray optics</title>

Capillary optics for radiation focusing

Aerial 3D LED display by use of retroreflective sheeting

Contact Info

Product

Resources

About