Focal Law Calculations for Annular Phased Array Transducers
نویسندگان
چکیده
One of the most important characteristics of annular arrays is their superior focal capabilities. In order to achieve the desired focussing, each of the elements is fired in different times. The delay times used for beam focussing are called focal laws. The focal laws are automatically calculated from the inspection software. In order to make sure that the focal laws are calculated correctly from the software, it is wise to validate the focal laws for a particular configuration. The validation/comparison will involve the calculation of focal law values using three different methods, from the experimental acquisition software (TWI software) and from simulation software (CIVA). Moreover, one of the methods introduces the concept of centre of mass as an exit point of the beam, which is novel to be investigated because previously only the geometric centre was considered for annular arrays.
منابع مشابه
Directivity Investigation of two Annular Phased Array Transducers
Abstract Annular phased array transducers are well known in the medical field, with their main use being in ophthalmology and dermatology, and have started to be employed in the NDT industry relatively recently. Annular arrays consist of a centre circular element and multiple ring-shaped elements of different width. This unique geometry of the probe makes it difficult to determine the generatin...
متن کاملEfficient Wideband Linear Arrays For Imaging And Therapy
transducer t o achieve a large intensity gain and deep penetration [1,2]. The fixed focused single element is mechanically moved in three dimensions to treat a volume. or akernatively in two dimensions snch as with annular arrays 13.41. IrnagiKq or monitoring performance with such transducers hay been limited due to their narrow bandwidt,h. low frequency, and/or need for mechanical scanning. M...
متن کاملInp2 - 2
A tactile display that provides tactile stimulation from a distance is studied. Hundreds of ultrasonic transducers cooperate to make a focal point of ultrasound based on phased-array focusing technique. It provides tactile feedback to floating images and natural user interfaces. It also tactually delivers characters, symbols, drawings, etc. to users.
متن کاملHigh power transcranial beam steering for ultrasonic brain therapy.
A sparse phased array is specially designed for non-invasive ultrasound transskull brain therapy. The array is made of 200 single elements corresponding to a new generation of high power transducers developed in collaboration with Imasonic (Besançon, France). Each element has a surface of 0.5 cm2 and works at 0.9 MHz central frequency with a maximum 20 W cm(-2) intensity on the transducer surfa...
متن کاملThe design of Delay Pulse Circuit for Ultrasonic Phased Array System
This paper presents the development of delay pulse circuit with 1ns resolution for both driving ultrasonic array transducers and digital receive beamforming for ultrasonic phased array system. The circuit which can supply pulses with a 1ns time resolution employs the phase shifting with phase locked loop (PLL). In this way, 6 phase clocks with 1ns phase difference are generated, which are used ...
متن کامل