Imaging properties of three refractive axicons

Abstract

The imaging properties of three types of refractive axicons are examined by using them in an imaging system. A linear axicon, a logarithmic axicon, and a Fresnel axicon are characterized by determining their point spread functions (PSFs) experimentally and by numerical simulation. The PSFs, which vary along the depth of field for the cases considered in the present investigation, are used in digital filters to denoise the images. A comparison of the imaging performance of these three optical elements is presented.

Two-photon scanned light sheet fluorescence microscopy with axicon imaging for fast volumetric imaging

“…However, postprocessing techniques, such as deconvolution or image filter processing, may be applied to improve the image quality. 36,37 Spherical aberration can also extend the axial extent of the detection PSF, 38 but the lateral resolution will loss in high NA system. 39,40 In Fig.…”

Bubble optics

“…Due to their peculiar properties (i.e. the line caustic), axicons exhibit an increased focal depth [36][37][38][40][41][42][43] . This corresponds precisely to the observations which triggered this investigation, now becoming readily comprehensible as phenomena of bubble axicons at work.…”

140 GHz Ultra-Long Bessel–Like Beam with Near-Wavelength Beamwidth

“…Various approaches have been developed to extend the DOF of the non-diffractive beam (e.g., axicon lens, narrow annular aperture filter, ring-lens, and computer-generated hologram) [11][12][13][14][15][16][17][18]. Among these methods, refractive axicons have better energy efficiency, considering the SNR [19][20][21]. As a result, axicons have been widely employed for generating the Bessel-Gauss beam in sub-THz and THz frequency ranges [7,9,[11][12][13].…”

“…Considering practical optic sizes, extending the DOF by the cone angles is more preferable. The concept of the cone angles decreasing during beam propagation has been previously reported with respect to Bessel-like beams having z-dependent cone angles, which are generated by a combination of conventional optical elements [19][20][21]. However, studies on the ultra-long DOF having a near-wavelength beam width have not been reported in the sub-THz and THz band.…”