Measurement of the 2 tensors of ktiopo 4, ktioaso 4, rbtiopo 4, and rbtioaso 4 crystals michael v. Yag beam and thus produce the halved wavelength of 532 nm green light. Yag laser has generated as high as above 66% efficiency for degenerately converting to 2120nm. Ktp may suffer from optical damage known as gray tracking. Nanosecond laser induced damage in nonlinear optical crystals. Schematic setup for frequency doubling experiments with lbo, ktp and bibo. This light is then focused onto a potassium titanyl phosphate ktp crystal to double its frequency and split the wavelength in half, producing a 532 nm wavelength. Potassium titanyl phosphate ktp is an inorganic compound with the formula ktiopo 4. Ktp532 laserassisted excision being a minimally invasive approach provides the advantage of minimal blood loss. Absolute measurement of the effective nonlinearities of ktp. We present our experience with the use of ktp 532 laser for this challenging disease.
An antireflection coating for ktp crystals at wavelengths 532. Yvo 4 and a ktp crystal is used for intracavity frequency doubling. The ktp 532 laser offers distinct advantages because it produces a zone of coagulation on either side of the incision, and as it cuts, it appears to seal the edges of the wounds. The weak absorption values of the ktp crystals were measured at 1064 nm and 532 nm by photothermal commonpath interferometer. Ktiopo4 ktp was chosen as the nonlinear optical crystal because of its high effective. This selective absorption of the green ktp laser beam by hemoglobin in tissue is the reason ktp laser vaporization prostatectomy was named photoselective vaporization of the prostate pvp.
Ktp is an important nonlinear optical material that is commonly used for frequencydoubling diodepumped solidstate lasers such as nd. Raicol produces ktp crystals with gray track resistance up to ten times greater than typical flux grown ktp. A ktp laser is a solidstate laser that uses a potassium titanyl phosphate ktp crystal as its frequency doubling device. A compact, solidstate, diodepumped laser at 532 nm stabilized in frequency on one of the electronic transitions r56 320 of the absorbing molecule 127 i 2 has been developed and investigated. Advantages large nonlinear optical nlo coefficients.
Yag laser energy to a 532 nm wavelength, which is in the green electromagnetic spectrum greenlightlaser and is selectively absorbed by hemoglobin and not at all by water. Other nonlinear crystals are available with short delivery times. Ktp crystal,ktp crystals,potassium titanyl phosphate. We supply super grade and customerdesigned ktp crystals for various applications. Ktp crystals potassium titanyl phosphate crystal eksma optics. There are several different configurations available to meet your needs. It has large nonlinear optical coefficients and wide angular bandwidth and small walkoff. This is possible due to advances in the controlled growth of ktp crystals, using proprietary modified fluxes and heat treatment. Yag laser with optoflex delivery system for treating benign pigmented lesions and tattoos 3. The ktp crystals, all type ii phase matched with propagation in. Ktps wide tuning range and high conversion efficiencies mean that short crystals can be used in this application. Dpssls have advantages in compactness and efficiency over other types, and high power dpssls have replaced ion lasers and flashlamppumped lasers in many scientific applications, and are now appearing commonly in green. Development of high efficiency second harmonic frequency converter. Ktp ktiopo4 is a nonlinear optical crystal, which possesses excellent nonlinear and electrooptic properties.
The output characteristics of 532 nm green laser using different doping concentrations and cavity configurations were investigated. Study of ktiopo4 graytracking at 1064, 532, and 355 nm b. Potassium titanyl phosphate ktp crystal photop ktp crystal is grown by improved flux growing technology and high purity chemical. Ktp crystals potassium titanyl phosphate crystal eksma. Mar 16, 2012 in this study, the fluxgrown ktp crystals with titanium from tio 2, ticl 4, and tioc 4 h 94, respectively, and the hydrothermalgrown ktp crystal were investigated.
The possibility of implementing angle, wavelength frequency, and temperaturenoncritical phase matching is shown. Another application well suited for ktp is quasi phase matching qpm. The first wavelength converter is ktp crystal, which has the ability to double the frequency of incoming nd. Ktp nonlinear crystal a crystal having a high electrooptic coefficient. Ktp crystal is mostly used as nonlinear crystals for frequency doubling of solidstate nd. Potassium titanyl phosphate ktiopo4 crystals ktp laser. At the end of 2008, the majority of articles published were based on the 80w ktp laser. Yag laser that has the spectral wavelength 1064nm to generate 532nm. The ktp crystal is engaged by a beam generated by a neodymium. Laserinduced photochromic damage in potassium titanyl phosphate.
Due to the large number of passes through the crystal, low insertion losses and high homogeneity are. The ktp laser beam can be fully transmitted through aqueous irrigants but is highly absorbed by hemoglobin inside prostatic tissue. High efficient, high peak power of 18kw with 4ns pulses of. Study of ktiopo graytracking at 1064, 532, and 355 nm. Zscan measurements of the anisotropy of nonlinear refraction. Experiment for frequency doubling with lbo, ktp and bibo crystals. This is directed through the ktp crystal to produce a beam in the green visible spectrum with a wavelength of 532 nm. The phasematching angles and effective nlo coefficient for opoopa pumped at 532 nm and 1064 nm in xz plane are showed as following figures. The pump wave at 532 nm is incident polarized along. General optics laser and passive qswitch crystals polarization optics nonlinear optics lasers and laser systems laser accessories and equipment optomechanics aperture dimensions, mm length, mm orientation.
Pdf in this paper, we tried to investigate to display the performance of the pure single potassium titanyl phosphate ktiopo3 or ktp crystal of. Potassium titanium oxide phosphate ktiopo 4, or ktp, is an efficient nonlinear optical crystal in the visible to infrared spectral region with relatively low cost. The effective nonlinear optical coefficient of ktp deff at 1064nm is. We report conditions that led to photochromic damage.
Greatly improved hf performance of ultrafast photodetectors in the wavelength range 800 to 2600 nm press release, pdf. Highenergy, highefficiency secondharmonic generation of. Optical properties of ktp crystals and their potential for. Pdf ktp532 laser in the management of rhinosporidiosis. Its large optical nonlinearity, damage resistance, wide acceptance angle, low insertion loss and thermally phasematching properties make ktp crystal suitable for frequency doubling of.
Generation of green second harmonic radiation in lbo, bibo. Recent progress made in the development of highenergy uv. Potassium titanyl phosphate ktp is an interesting crystal for many applications in nonlinear optics and electrooptics. Efficient 532 nm laser using high graytracking resistance ktp crystal article in laser physics 204. Potassium titanyl phosphate ktp crystals photonic solutions. Ktp is a standard crystal mostly used in extracavity configuration when a single pass through the crystal is required. Ylf laser, ktp plays an important role in parametric sources for tunable output from visible 0.
Pdf study second harmonic generation of ktp crystal. The process of the gray track formation is cumulative and leads to deterioration of harmonic conversion. One 532 nm wavelength beam is incident on the small seeder ristra opo. We have studied graytracking induced by a pulsed and polarized 532 nm laser beam in flux grown ktiopo 4 ktp crystals. High gray track resistance crystals hgtr ktp advantages average output power density at 532 nm up to 5 kw cm. We supply standard ktp crystal and customerdesigned ktp crystal for various applications. It can be tailor made for all nonlinear applications within the transparency range of ktp, without the phase matching limitations of bulk ktp. Efficient 532 nm laser using high graytracking resistance. Crystals for stimulated raman scattering kgw, ba no32. Potassium titanyl phosphate ktp crystals casixs ktp crystals feature high purity, low absorption at fundamental and second harmonic generation wavelengths. Ktiopo4 crystals ktp ktp is a nonlinear optical crystal, which possesses excellent nonlinear and electrooptic properties.
The deffs were derived from the parametric gain of an 800nm signal wave in the sample crystals when they were pumped by the frequencydoubled, spatially filtered light from an injectionseeded, qswitched nd. Continuouswave 532nmpumped singly resonant optical. As an efficient opo crystal pumped by the fundamental and second harmonics of a nd. The third 532 nm beam is used for mixing with 803 nm in a lbo. It has large nonlinear optical coefficients and wide angular bandwidth and small walkoff angle,etc. Pdf optical studies of laserinduced graytracking in ktp. An energy conversion efficiency of 80% for secondharmonic generation of 532 nm radiation from 1064nm radiation has been achieved with a single ktp crystal and a commerical injectionseeded qswitched nd. Potassium titanyl phosphate single crytal, known as ktp ktiopo4, is the most efficient frequency doubling crystal for nd. It uses a high graytracking resistance ktp crystal as nonlinear optical crystal. Ktp 532 laser in the management of rhinosporidiosis. Maintaining ktp crystal at an elevated temperature e. Crystals for stimulated raman scattering kgw, bano32.
The laserscope ktp532 yag laser is an affordable and easy to use system that can be used for cosmetic treatments of facial and leg veins, acne, and vascular skin lesions. Self qswitched laser pulse at 532 nm with high peak power of 96 w, pulse width of 88 ns at fwhm and. Measurement of the 2 tensors of ktiopo4, ktioaso4, rbtiopo4. The ktp532 laser offers distinct advantages because it produces a zone of coagulation on either side of the incision, and as it cuts, it appears to seal the edges of the wounds.
The older 80w laser device uses the ktp crystal, and the latest generation uses the lbo crystal with a 120w power setting. A potassiumtitanylphosphate ktp crystal doubles the frequency of pulsed neodymium. Nonlinear crystals available from stock detailed datasheet, pdf large quantities of the mostly used nonlinear crystals like lbo, bbo, bibo and ktp are available from stock. Crystals free fulltext frequency conversion in ktp. Ktp is the best nonlinear optical crystal for 1064nm pumped opos. New models of ultrafast photodiodes have been released by alphalas gmbh. Ktp crystal, potassium titanyl phosphate crystal, ktiopo4. Yag laser has generated above 66% efficiency for degenerately converting to 2120nm. Pdf in this paper, we tried to investigate to display the performance of the pure single. Under certain conditions, the conversion efficiency was reported to 80%, which leaves other nlo crystals. Average output power density at 532 nm up to 5 kw cm. Yag laser through a potassium titanyl phosphate crystal, which doubles the frequency and halves the wavelength to 532 nm, producing a beam in the bright green visible spectrum that has a tissue penetration of 0.
Ktp crystals resist the graytrack laser damage in secondharmonic generation applications. The evolution of ktp laser vaporization of the prostate. Increasing the temperature of ktp crystal can enhance the damage threshold of ktp crystal. Study on the weak absorption of potassium titanyl phosphate. Please refer here for more information on the oven for crystal. Second harmonic output power at 532 nm versus lens focal length. The new photodetectors expand the product range towards faster rise times as short as 15 ps and wider spectral ranges from 170 to 2600 nm.
The parametric process uses type ii noncritically phasematched interaction. The ktp crystal and its isomorphs belong to mm2 pointgroup symmetry, with the mutual orientation of the axes xyzabc. Diodepumped solidstate lasers dpssls are solidstate lasers made by pumping a solid gain medium, for example, a ruby or a neodymiumdoped yag crystal, with a laser diode. Ktp crystal also has high electroopticeo coefficient and low dielectric constant, and large figure of merit, these features. The highquality bulk potassium titanyl phosphate ktiopo 4 or ktp crystals have been grown successfully by the hydrothermal method using an improved mixed solution of k 2 hpo 4 2. Azure provides precision oven with temperature controller for heating ktp. The second 532 nm is used to pump the big ristra opo. Ktp crystals are optimized for shg intracavity configuration in low peak power cw lasers. Ktp crystal and its isomorphs for all frequency conversion tasks including generation of harmonics and sum and difference frequencies, as well as parametric generation in the range of their transparency 0. Absolute magnitudes of the effective nonlinearity, deff, were measured for seven ktp and six bbo crystals. Ktp crystals are optimised for shg intracavity configuration in low peak power cw lasers. The ktp laser is generated by passing the light of a rapidly pulsed nd. These hgtr ktp elements are suitable for high power density applications.
A secondharmonic output of 720 mj was generated with 900 mj of incident 1064nm radiation at 10 hz. Ktp was first introduced as the nlo crystal for nd doped laser systems with high conversion efficiency. Transmission spectra measured under polarized light give. A ld endpumped acousticoptic qswitched intracavity frequencydoubled nd. This experiment proves that 532 nm can alone graytrack ktp. The effective nonlinear optical coefficient of ktp deff at 1064nm is more than 1. Its effective non linear coefficient is about three times larger than that of bulk ktp. Yvo4 crystal laser, as it has large nonlinear optical coefficients, wide angular bandwidth and small walkoff angle, broad temperature and spectral bandwidth. Growth and optical properties of bulk ktp crystals by. Clinical applications of the 532nm diode laser for the. It is featured with extreme low absorption at the fundamental and second harmonic generation wavelengths. Ktp s opo results in stable, continuous outputs of femtosecond pulse of 108 hz repetition rate and miliwatt average power levels in both signal and idler output. Crystals potassium titanyl phosphate ktp crystals casixs ktp crystals feature high purity, low absorption at fundamental and second harmonic generation wavelengths.
Ktp crystal a crystal used as modulators and qswitches. Smith we use the separatedbeams method to measure the secondorder nonlinear optical tensors of the crystals. The conversion efficiency to 532nm is up to 60% at 250 mw cm. We report the results of an analysis of the functional capabilities of the ktp crystal and its isomorphs for nonlinearoptical frequency conversion of all types of interactions in the transparency range of the crystal. Test report for the radiation testing of non linear crystals christian poivey1, volker leonhardt2, scott kniffin1, paul marshall3, jordan camp2 1 mei 2 nasagsfc 3 consultant introduction non linear crystals will be used for second harmonic generation in the lisa laser system the effect of. In this process zoriented waveguides of ktp are periodically poled and pumped with diode lasers to generate blue to near uv wavelengths. An antireflection coating for ktp crystals at wavelengths 532 and 1064 nm. Yvo 4 laser and nonlinear optics wear laser goggles at all times during this experiment. Periodically poled ktp is an entirely new type of nonlinear material. Due to the large number of passes through the crystal, low insertion losses and high homogeneity are essential for conversion efficiency. Typical spectra of the incident and generated second harmonic radiation. Ktp crystal ktiopo 4 crystals nonlinear crystals ktp crystal.
1092 1009 1431 1443 1330 147 1509 169 1525 23 1075 473 771 1187 248 301 761 888 1490 695 876 240 964 420 790 1017 455 373 1169 1126 1583 270 15 293 1266 277 1361 1476 103 61 519 420 624 937 202 1464 1325 1289