Bessel

Bessel generates a Bessel beam. This Gain is based on the paper by Hasegawa et al. 1.

use autd3::prelude::*;
fn main() {
let x = 0.;
let y = 0.;
let z = 0.;
let nx = 0.;
let ny = 0.;
let nz = 0.;
let theta = 0. * rad;
let _ = 
Bessel {
    pos: Point3::new(x, y, z),
    dir: UnitVector3::new_normalize(Vector3::new(nx, ny, nz)),
    theta,
    option: BesselOption {
        intensity: EmitIntensity::MAX,
        phase_offset: Phase::ZERO,
    },
};
}
#include<autd3.hpp>
int main() {
using namespace autd3;
const auto x = 0.0;
const auto y = 0.0;
const auto z = 0.0;
const auto nx = 0.0;
const auto ny = 0.0;
const auto nz = 1.0;
const auto theta = 0.0;
Bessel(Point3(x, y, z), Vector3(nx, ny, nz), theta* rad,
       BesselOption{
           .intensity = std::numeric_limits<EmitIntensity>::max(),
           .phase_offset = Phase::zero(),
       });
return 0; }

using AUTD3Sharp;
using AUTD3Sharp.Utils;
using AUTD3Sharp.Gain;
using static AUTD3Sharp.Units;
var x = 0.0f;
var y = 0.0f;
var z = 0.0f;
var nx = 0.0f;
var ny = 0.0f;
var nz = 1.0f;
var theta = 0.0f;
new Bessel(
    pos: new Point3(x, y, z),
    dir: new Vector3(nx, ny, nz),
    theta: theta * rad,
    option: new BesselOption
    {
        Intensity = EmitIntensity.Max,
        PhaseOffset = Phase.Zero
    }
);

from pyautd3 import Bessel, BesselOption, EmitIntensity, Phase, rad

x = 0.0
y = 0.0
z = 0.0
nx = 1.0
ny = 0.0
nz = 0.0
theta = 0.0
Bessel(
    pos=[x, y, z],
    direction=[nx, ny, nz],
    theta=theta * rad,
    option=BesselOption(
        intensity=EmitIntensity.MAX,
        phase_offset=Phase.ZERO,
    ),
)

Here, pos is the apex of the virtual cone (dotted line in the figure below) that generates the beam, dir is the direction of the beam, and theta is the angle between the plane perpendicular to the beam and the side of the virtual cone that generates the beam ( in the figure below).

Bessel beam (cited from the paper by Hasegawa et al.)

Optionally, you can specify the output intensity and phase offset. The default values are as above.

1

Hasegawa, Keisuke, et al. “Electronically steerable ultrasound-driven long narrow air stream.” Applied Physics Letters 111.6 (2017): 064104.