Aspherical X-Ray Optics
Parallax makes ‘extreme’ aspherical reflective x-ray optics by means of electroforming replication process. Examples include compound parabolic concentrators, x-ray / EUV grazing incidence optics and other shapes with axial symmetry. Our particular specialty is optics with very high aspect ratios (length / diameter), often over 100X. Optics can resemble tapered hollow needles with accurate inside reflective surface shapes. Optics that are less extreme can resemble truncated cones with diameters up to 3” (7.5 cm) and as long as 13 cm. Parallax can produce surface roughness below 10 Angstroms RMS in various types of reflective coating materials including Au, Pd, Ni, Pt and others. Thickness of these reflecting shells can be as small as .025 mm and as thick as 1 mm. The outer electroformed shell material can be either Cu or Ni.
If your application calls for focusing, concentrating, parallelizing, collimating, or manipulating x-rays from the 100eV to 5000eV range and you’d like to find out more how Parallax technology can help you, please contact us to discuss it with our technical staff.
Applications
- Compound Parabolic Concentrators
- Light pipes
- X-ray focusing
- X-ray collimation
- EUV optics
- X-ray optics including Wolter 1 type optics
- Cold neutron optics
- IR optics
- Laser scalpel tips
- Cold Shields
Basic Specifications
- Reflector thickness
- Maximum diameter
- Minimum diameter
- Maximum length
- Typical Roughness, RMS
- Reflector materials
- 0.025 -1 mm
- 7.5 cm
- 0.025 mm
- 14 cm
- 10 Angstroms
- Au, In, Ni, Pd, Cu and others
The Importance of Low Reflecting Surface Roughness:
Although the surface roughness of an optic’s reflecting surface may be considerably less than the wavelength of light passing through it, roughness can still cause photons to scatter in unwanted ways. To achieve maximum signal to noise ratio, roughness of reflective surfaces should be minimized. Parallax specializes in production of ultra-low roughness surfaces in our optics. We have achieved roughness as low as 5 Angstroms RMS in some cases, with 10 Angstroms being typical.
Multiple Reflectors:
Optics such as Wolter 1 reflectors can be made where radiation reflects first from one type of surface and then from another. These reflectors can be highly nested in coaxial manner to fill an aperture as shown in the figure below:
Miniaturized Optics:
Parallax can make extremely small electroformed replicated optics for various applications such as:
- Transferring light from a fiber of larger numerical aperture (n.a.) to a fiber of lesser n.a.
- Coupling ambient light to a fiber optic
- Manufacturing very small x-ray optics
The size of these optics can be unexpectedly small and some examples are shown in the image below:
Examples of Extreme Aspherical Optics by Parallax:
A US nickel is shown for comparison,center. The long thin optic at the top is a Grazing Incidence Parabaloid (GIP) with a 1 mm entrance aperture and roughly 2 mm exit aperture and is 6.5 cm long. Clockwise from there, in the brass holder is a Compound Elliptical Concentrator (CEC) for low energy x-rays. Next is a Compound Parabaloid Concentrator (CPC) for IR followed by another GIP for x-rays. Finally, at about ten o’clock is another CEC for x-rays with a small aperture of 25 microns. These optics are replicated from highly polished male mandrels of very precise computer-designed shape. Reflective coatings of Au, Ni, Cu, Ag, Pd, and Pt are available with others by special request. Wall thickness can be anywhere from 50 microns to 500 microns.
Parallax Research Inc. Awarded Patent for New ‘X-Ray Monochromator’ Optic
Parallax Research, Inc. has recently been awarded US Patent # 7,412,030 B1 for a new x-ray monochromator focusing optic that produces intense monochromatic x-ray beams. The technology is the result of Parallax’s extensive expertise with x-ray optics design and fabrication.
The new optic can be particularly useful for production of small focused spots of monochromatic x-rays for X-Ray Diffraction or X-Ray Fluorescence applications. It can also be used on the detection side to enhance collection of x-rays of a specific narrow energy range and focus them to a detector. The useful energy range of the device is from 100eV to 12,000eV (12KeV) and the bandwidth of monochromatic energy is 50eV or less, depending on the diffractor used.
The new Parallax optic has a unique compound optic / diffractor design. A rotated paraboloid metal cone collects a large solid angle of diverging x-rays from a small spot source, such as a sample or x-ray tube anode, and then directs a ‘parallelized’ conical x-ray beam to a diffractor ring. The diffractor ring then focuses the x-rays into a high-flux monochromatic beam with spots as small as 50 microns in diameter. The size of the optic can be up to 3 inches maximum length and 2 inches maximum diameter.
An example application, sulfur in oil, using the x-ray collimator optic is illustrated in the diagram below. This spectrometer kernel uses a Moxtek Magnum x-ray source in transmission mode, a sample flow-cell, a graphite ring diffractor, and a Parallax proportional counter. There are many other possible applications using a variety of configurations of x-ray tube and diffractors.
The new technology is intended for both OEM and end-user applications in XRF and XRD. Please contact Parallax Research for further information and details.
Parallax: Pioneering New X-Ray Perspective!