In this study, we manufactured a 460 mm long deformable mirror which has 28 channel-PZTs on the ellipse pre-figured mirror and flat back surfaces. We evaluated the LTP target ellipse shape measurement result and the "junction" effect by applying voltage to each electrode.
We have developed an X-ray zoom condenser optical system using deformable mirrors that can adjust the beam size by deformation of their shape. The shapes of deformable mirrors are changed by a combination of mechanical and piezoelectric bending. Large deformations up to third order polynomials are achieved by mechanical bending. More precise shapes are achieved by piezoelectric bimorph mirror. However, because both ends of the mirror are mechanically clamped, capability of deformation by piezoelectric bending is lower than that of free-standing piezoelectric bimorph mirrors. So, we propose a bending method that tunes the mechanical bending conditions to intentionally leave the optimized shape error to be easily compensated by the piezoelectric bending process.
Various types of X-ray focusing optical systems are used at X-ray synchrotron radiation and free-electron laser facilities. However, these are designed for specific purposes and fixed optical parameters such as the numerical aperture (NA). Their lack of adaptability limits their application targets. In this research, we developed an X-ray adaptive focusing optical system which can control the beam size without moving the position of focus. The optical system consists of two deformable mirrors in one dimension. To vary the focused beam size, the NA is controlled by deforming the shape of the mirrors from concave to convex. The results will be presented along with the aberration properties estimated by ray trace and wave optical methods.
In synchrotron radiation facilities and X-ray free electron laser facilities, beam size adjustment depending on the experimental condition and the sample size is necessary. Various types of X-ray focusing optical systems are used for beam conditioning. However, they are specially designed for specific purposes and optical parameters such as numerical aperture (NA) and focal length are fixed. This lack of adaptability has limited application targets. In this research, we are developing X-ray adaptive focusing optical system which can control the beam size without moving the position of the focus. The optical system consists of two deformable mirrors in one dimension. In order to control the focused beam size, the NA can be controlled by deforming the mirror shapes from concave to convex. When we want to achieve large NA, deform the upstream mirror into convex shape and spread the beam. The downstream mirror receives X-ray with full aperture and X-ray is focused at focal point. When we want to achieve small NA, deform the upstream mirror into a concave shape and narrow down the reflection area of downstream mirror. NA becomes small because reflection area of downstream mirror becomes narrow. One dimensional focusing experiment of large NA adaptive optical system was performed at SPring-8 as a demonstration. A focused beam with an intensity profile having a full width at half maximum of 134 nm was achieved at 10 keV. This is close to ideal beam size. In my presentation, I will explain details of adaptive focusing optics and deformable mirrors.