http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate Support for the k-Wave MATLAB toolbox en-US Tue, 12 May 2026 23:28:24 +0000 http://bbpress.org/?v=1.0.2 q http://www.k-wave.org/forum/search.php http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5876 Tue, 04 Apr 2017 09:45:27 +0000 Bradley Treeby 5876@http://www.k-wave.org/forum/ <p>Hi Andrew,</p> <p>Glad you managed to figure it out!</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5869 Thu, 23 Mar 2017 16:48:28 +0000 ad000000 5869@http://www.k-wave.org/forum/ <p>Oops. Now I see. It's because the makeCircle command is entered in units of grid points. </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5868 Wed, 22 Mar 2017 19:19:12 +0000 ad000000 5868@http://www.k-wave.org/forum/ <p>p.s. my full name is Andrew Draudt </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5867 Wed, 22 Mar 2017 19:17:42 +0000 ad000000 5867@http://www.k-wave.org/forum/ <p>Thanks Brad. Oh yeah, 2-d.<br /> What about the change caused by increase in Nx and Ny?</p> <p>Thanks for the paper link. Interesting - the H101 was the same transducer I modeled a lot in my grad work.<br /> -Andy </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5866 Wed, 22 Mar 2017 09:27:35 +0000 Bradley Treeby 5866@http://www.k-wave.org/forum/ <p>Hi Andy,</p> <p>This example is in 2D, so you will get a different field compared to the O'Neil solution. An arc in 2D is equivalent to a cylindrically focused rectangle in 3D (think of the arc infinitely extended out of the page).</p> <p>If you define a focused bowl, k-Wave should give very good agreement. See <a href="http://bug.medphys.ucl.ac.uk/papers/2016-Martin-IEEETUFFC.pdf">this paper</a> for an example which compares k-Wave with the O'Neil solution and experimental measurements made using a focused bowl transducer.</p> <p>Brad. </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5864 Tue, 21 Mar 2017 20:26:03 +0000 ad000000 5864@http://www.k-wave.org/forum/ <p>p.s. why does increasing Nx and Ny change the field shape on this example? </p> http://www.k-wave.org/forum/topic/focused-field-example-is-innacurate#post-5863 Tue, 21 Mar 2017 20:04:42 +0000 ad000000 5863@http://www.k-wave.org/forum/ <p>Hi. This software looks so promising! Thanks.<br /> However, when I calculated the true field pattern (using O'Neil's method, for example) of the transducer in the example "Simulating transducer field patterns" , I get a field with far more lobes and nearfield maxima (and less strong) than the K-Wave results. Also, the K-Wave output shows maxima and minima on the surface of the transducer - where it is supposed to be constant.<br /> Any insights would be appreciated!<br /> Thanks,<br /> Andy </p>