http://www.k-wave.org/forum/topic/focused-transducer-pressure-field-distribution-simulation Support for the k-Wave MATLAB toolbox en-US Wed, 13 May 2026 01:50:21 +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-transducer-pressure-field-distribution-simulation#post-4545 Fri, 23 May 2014 09:08:05 +0000 Bradley Treeby 4545@http://www.k-wave.org/forum/ <p>Hi Lin,</p> <p>For a single element transducer, I would define the source explicitly rather than using <code>makeTransducer</code>. For a focused transducer, there are two possibilities. First, you could create a curved transducer with the correct radius so that the ultrasound waves are geometrically focused (for example, using <code>makeSphericalSection</code>). Second, you could create a flat transducer and set the correct focus position using time delays. For example:</p> <pre><code>% define a circular source element source_radius = 15; % [grid points] source_shape = makeDisc(Nx, Ny, Nx/2, Ny/2, source_radius); % assign source element to source mask source_z_pos = 12; % [grid points] source.p_mask = zeros(Nx, Ny, Nz); source.p_mask(:, :, source_z_pos) = source_shape; % define source input source_freq = 2e6; % [Hz] num_cycles = 5; source_signal = toneBurst(1/kgrid.dt, source_freq, num_cycles); % create time delays to focus the transducer and assign to source focus_position = [0, 0, 0]; % [m] source.p = focus(kgrid, source_signal, source.p_mask, focus_position, c0);</code></pre> <p>Brad. </p> http://www.k-wave.org/forum/topic/focused-transducer-pressure-field-distribution-simulation#post-4544 Fri, 23 May 2014 06:09:42 +0000 huanglin 4544@http://www.k-wave.org/forum/ <p>Sorry, I just made a mistake, when I set transducer.radius = limited number in Ultrasound Beam Patterns Example, it reminded me that Only a value of transducer.radius = inf is currently supported. </p> http://www.k-wave.org/forum/topic/focused-transducer-pressure-field-distribution-simulation#post-4543 Fri, 23 May 2014 04:45:00 +0000 huanglin 4543@http://www.k-wave.org/forum/ <p>Hi Dr.Brad Treeby,</p> <p> I am a fresh man for ultrasound imaging. Now I want to compute the pressure field distribution of a single element focused transducer in 2D or 3D, and I have tried both Ultrasound Beam Patterns Examples (I chosed transducer.number_elements = 1, I also modified the transducer.element_length with our transducer length and set transducer.radius = R, I do not know if this example is correct for a curved single element transducer simulation? ) and Transducer Field Patterns Example (I just know the focal length of our transducer, and I used R=2*f for calculation R. Therotically, a spherical curved transducer has focusing capability, I think this example is more suitable for my purpose) for simulation. Furthermore, is there any examples for focused transducer temperature distribution simulation?<br /> Please let me know which example is correct for my computation?</p> <p>Thanks,<br /> Lin </p>