High efficiency Ka-band second-harmonic peniotron

Author(s):  
L.J. Dressman ◽  
D.B. McDermott ◽  
Y. Hirata ◽  
D.A. Galoagher ◽  
N.C. Luhmann
2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Yu Zhai ◽  
Ding Xu ◽  
Yan Zhang

This paper presents a lightweight, cost-efficient, wideband, and high-gain 3D printed parabolic reflector antenna in the Ka-band. A 10 λ reflector is printed with polylactic acid- (PLA-) based material that is a biodegradable type of plastic, preferred in 3D printing. The reflecting surface is made up of multiple stacked layers of copper tape, thick enough to function as a reflecting surface (which is found 4 mm). A conical horn is used for the incident field. A center-fed method has been used to converge the energy in the broadside direction. The proposed antenna results measured a gain of 27.8 dBi, a side lobe level (SLL) of −22 dB, and a maximum of 61.2% aperture efficiency (at 30 GHz). A near-field analysis in terms of amplitude and phase has also been presented which authenticates the accurate spherical to planar wavefront transformation in the scattered field.


Optics News ◽  
1988 ◽  
Vol 14 (12) ◽  
pp. 20
Author(s):  
W. J. KOZLOVSKY ◽  
C. D. NABORS ◽  
R. L. BYER

2020 ◽  
Vol 8 ◽  
Author(s):  
Ning Ma ◽  
Meng Chen ◽  
Ce Yang ◽  
Shang Lu ◽  
Xie Zhang ◽  
...  

We report high-energy, high-efficiency second harmonic generation in a near-infrared all-solid-state burst-mode picosecond laser at a repetition rate of 1 kHz with four pulses per burst using a type-I noncritical phase-matching lithium triborate crystal. The pulses in each burst have the same time delay ( ${\sim}1~\text{ns}$ ), the same pulse duration ( ${\sim}100~\text{ps}$ ) and different relative amplitudes that can be adjusted separately. A mode-locked beam from a semiconductor saturable absorber mirror is pulse-stretched, split into seed pulses and injected into a Nd:YAG regenerative amplifier. After the beam is reshaped by aspheric lenses, a two-stage master oscillator power amplifier and 4f imaging systems are applied to obtain a high power of ${\sim}100~\text{W}$ . The 532 nm green laser has a maximum conversion efficiency of 68%, an average power of up to 50 W and a beam quality factor $M^{2}$ of 3.5.


Sign in / Sign up

Export Citation Format

Share Document