Videos Set-up construction and operation Construction and operation of a standard optical tweezers. Construction and operation of a holographic optical tweezers. Construction and operation of a speckle optical tweezers. Geometrical optics Brownian motion in an optical trap (low NA). Brownian motion in an optical trap (medium NA). Brownian motion in an optical trap (high NA). Scattering of a ray on a spherical particle (high refractive index). Scattering of a ray on a spherical particle (low refractive index). Trapping efficiencies (high refractive index). Trapping efficiencies (low refractive index). Alignment for a prolate ellipsoidal particle. Kramers’ transitions in a double optical trap. Transversal optical trapping: NA=0.50 nm=1.33 np=1.50. Transversal optical trapping: NA=1.00 nm=1.33 np=1.50. Transversal optical trapping: NA=1.30 nm=1.33 np=1.50. Axial optical trapping: NA=0.50 nm=1.33 np=1.50. Axial optical trapping: NA=1.00 nm=1.33 np=1.50. Transversal optical trapping: NA=1.30 nm=1.33 np=1.50. Transversal optical trapping: NA=0.50 nm=1.33 np=1.00. Transversal optical trapping: NA=1.00 nm=1.33 np=1.00. Transversal optical trapping: NA=1.30 nm=1.33 np=1.00. Axial optical trapping: NA=0.50 nm=1.33 np=1.00. Axial optical trapping: NA=1.00 nm=1.33 np=1.00. Axial optical trapping: NA=1.30 nm=1.33 np=1.00. Axial optical trapping: NA=0.50 nm=1.60 np=1.00. Transversal optical trapping: NA=1.00 nm=1.60 np=1.00. Transversal optical trapping: NA=1.30 nm=1.60 np=1.00. Transversal optical trapping: NA=0.50 nm=1.60 np=1.00. Axial optical trapping: NA=1.00 nm=1.60 np=1.00. Axial optical trapping – NA=1.30 nm=1.60 np=1.00.