Rumored Buzz on a-BBO Crystal
Rumored Buzz on a-BBO Crystal
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The crystal axis is c. The Main ray is parallel for the course used to measure the tuning angle (θ), which happens to be optimized during period matching. Conversion efficiency is optimized for rays parallel on the Main ray and worse for rays at much larger angles (ψ) to your chief ray.
A2: Of course, extended publicity to humidity can degrade the optical performance of BBO crystals. Humidity can lead to water absorption on the crystal surface area, that may impact its optical properties.
A next issue is that the group velocity mismatch among the second harmonic and fundamental-frequency pulses will lead to one pulse lagging another as The 2 propagate. This is named temporal wander-off and may manifest even under best period-matched problems.
On the other hand, it’s imperative that you note that even though BBO crystals can handle high power, they should still be made use of in just their specified energy vary to prevent possible injury and be certain optimal effectiveness.
We use Numerical Aperture (NA) to explain the extent of this angular written content. Ideally, the elemental laser mild could be collimated throughout the crystal, considering the fact that collimated gentle resembles a bunch of rays aligned to the identical direction with an NA of zero.
Now Assess the most power density to that that is specified since the LIDT for that optic. If the optic was examined in a wavelength in addition to your functioning wavelength, the damage threshold has to be scaled properly.
Even though the examination benefits are only representative of 1 coating operate, Thorlabs specifies destruction threshold values that account for coating variances.
When an optic is damaged by a constant wave (CW) laser, it is usually mainly because of the melting of the surface on account of absorbing the laser's energy or damage to the optical coating (antireflection) [1]. Pulsed lasers with pulse lengths for a longer period than 1 µs may be handled as CW lasers for LIDT discussions.
Assuming a crystal of the specified thickness, it is feasible to define a reference pulse which has a spectral selection which is the most which can be adequately period matched. This spectral bandwidth limitation can also be considered regarding an SHG spectral filter whose passband depends on equally the precise crystal and the pulse's Middle frequency. Frequencies outside of this filter’s passband is going to be rejected from going through the SHG system.
Fluorescence excitation is an additional realm the place the 266nm technology showcases its significance. Fluorescence involves the absorption of sunshine by a cloth and the following emission of light at a special wavelength. The 266nm mild is website highly effective in exciting certain fluorescent materials, building them glow brightly and letting for his or her detection and examine.
It really is widely useful for nonlinear frequency conversion while in the ultraviolet, noticeable, and around-infrared. The BBO crystal may be the most critical nonlinear crystal for in the vicinity of-infrared optical parametric chirped-pulse amplifiers, which presently supply couple of optical cycle pulses with significant typical and ultrahigh peak powers.
This characteristic translates to diminished will need for considerable thermal administration units, again accentuating Charge financial savings and program simplicity.
Thermal fluctuations are a concern in many experimental and industrial setups. Yet, BBO crystals�?intrinsic thermal steadiness makes sure that they don’t just survive but prosper in these types of disorders.
Pulsed lasers with superior pulse repetition frequencies (PRF) could behave likewise to CW beams. Regretably, this is very dependent on aspects such as absorption and thermal diffusivity, so there isn't a reliable process for identifying any time a superior PRF laser will injury an optic due to thermal consequences.