Surgical method of treating low-activity fibrovascular membrane with replacing defect of retinal pigment epithelium
SUBSTANCE: invention refers to medicine, particularly ophthalmology, and can be used to treat a low-activity fibrovascular membrane of the macular area. The method involves performing subtotal vitrectomy, removing the fibrovascular membrane, packing the retina with a perfluoroorganic compound followed by replacing by air and SF6 gas in an amount of 2 ml and performing and a laser endolasercoagulation of the retina. That is preceded by performing iridectomy and separating the pigment layer of the diameter of 1 mm. That involves preparing a suspension of 0.85% NaCl 0.2 ml and the pigment layer. The prepared suspension is introduced to replace the removed fibrovascular membrane before packing the retina with the perfluoroorganic compound and performing endolasercoagulation.
EFFECT: using the invention provides the partial restoration of the morphological structure and functional adequacy of the retina involved into the developing fibrovascular tissue.
The invention relates to the field of medicine, particularly ophthalmology, and can be used for the treatment of fibrovascular membranes low activity in the macular region with simultaneous replacement of the defect pigment epithelium of the retina.
Fibrovascular membrane - pathological entity, which is the outcome of this pathological process, as subretinal neovascularization. Most often this pathology manifests itself in the pathology of the foveolar area, particularly in age-related macular degeneration of the retina. In the process of developing neovascular tissue in the Central section of the retina is the proliferation of fibrovascular tissue, replacing the area of neovascularization. The formation of fibrovascular membranes accompanied by severe deformation and atrophy of the pigment epithelium of the retina, and therefore even antimajoritarian therapy often has low efficiency. In addition, angiogenesis blockers can reduce the growth of blood vessels, reducing the area of likeda foveolar tissue. When this area of fibrosis is not amenable to reduction. This leads to the fact that the main therapies of fibrovascular membranes is the surgical removal of the macular area [Bikbov M. M., Faizrakhmanov P. P., Yarmuhametov A. L. the Effectiveness of submacular surgery fibrovascular the membranes in wet form of age-related macular degeneration // Cataract and refractive surgery. - 2013. - So 13. No. 2. - S. 41-44].
From the point of view of morphology, pigment epithelium is located between choriocapillary layer of the choroid and retina plays an important role in photoreception, the formation and metabolism of the latter. Pigment epithelium of the retina becomes pigmented epithelium of the ciliary body and iris, based on their inner surface. The main reason for the development of fibrovascular membranes low activity and neovascularization in the Central section of the retina with age-related macular degeneration is a defect in Bruch's membrane and retinal pigment epithelial. This leads to the fact, that to preserve the visual function of the pigment epithelium of the iris is able to replace the pigment epithelium of the retina, while keeping its functionality.
The prototype of the invention is a method of surgical treatment of fibrovascular membranes of low degree, based on the removal of the membrane from its localization with the use of vitrectomy, retinotomy [Zakharov C. D. - M.: vitreoretinal surgery, 2003]. This method will include the assessment Subtotal vitrectomy, retinotomy the macular region in the projection point of the membrane and its subsequent removal of the subretinal space, as well as the use of tampons vitreal cavity of gas and air. However, the functional is the playing technique is similar to the operation is low, in 27% of cases promptly after treatment visual acuity deteriorates. In addition, in some cases, possible relapse. This low functional result because of fibrovascular tissue in his education partly replaces the pigment epithelium of the retina. After surgical treatment from the point of view of morphology in the foveolar area is located choriocapillary layer of the choroid and deformed layer of photoreceptors. In order to restore the integrity of the destroyed layer retinal pigment epithelial attempted transplantation under the macula cells of the pigment epithelium, aspirated from the peripheral regions of the retina of the patient. However, additional damage to the retina in this procedure, the technical complexity in the formation of the flap pigment epithelium of the retina and the absence of conclusive data about the viability of the transplanted cells contributed to the lack of wide dissemination methods.
The objective of the invention was to develop a method of surgical treatment of fibrovascular membranes low activity, replacing the defect retinal pigment epithelial involved area plot of the pigment epithelium of the iris.
The proposed method of treatment is the removal of fibrovascular membrane is autologous cells of the pigment epithelium of the iris of the eyeball in the affected area of the retina.
The technical result when using the invention, the partial restoration of the morphological structure and the functional usefulness of the area of the retina affected by the development of fibrovascular tissue.
The indication for this method of treatment is fibrovascular membrane low activity with clear boundaries with no signs of edema.
The proposed method of surgical treatment of fibrovascular membranes low activity is carried out in 4 stages.
stage 1. The fence section of leaf pigment epithelium of the iris of the affected eye.
Fence pigmented sheet of the iris is carried out as follows. Form 1 tunnel incision. Filling the anterior chamber with viscoelastic, vitreal scissors 25G form the basal iridotomy iris not less than 1 mm in diameter. Collected material is evacuated from the anterior chamber of the retinal forceps 25G. Separate the pigment epithelium, forming a layer of pigment cells 1 mm in diameter. The cells of the pigment epithelium of the iris is placed in a sterile tube containing 0.2 ml of 0.85% NaCl. The contents of the tubes fill the syringe with a volume of 1 ml By passing the solution with the pigment epithelium through a needle, forming a suspension, due to the fact that cells lose touch under mechanical impact.
stage 2. Holding vitreoretinal the intervention in volume Subtotal vitrectomy using the standard method. Is a three port 25G vitrectomy with removal of the rear hyaloid.
stage 3. Holding retinotomy. Retinotomy is from the temporal side in the area of the projection of the edges of fibrovascular membane to the imaging region. The length of retinotomy must be more than 50% of the radius of the membrane for further evacuation. Then with the help of curved peaks perform the mobilization of the membrane. The membrane is removed by means of horizontally curved tweezers formed through retinotomies hole. The bleeding stopped, lifting the bottle of infusion solution and thereby increasing the intraocular pressure.
stage 4. Irrigation suspension of the pigment epithelium. The suspension of cells of the pigment epithelium of the iris is injected through retinotomy in the location area of fibrovascular membranes in full, thus after removal of fibrovascular tissue is restored to the pigment layer of the retina. Produce tamponade of the retina performancesin connection. Retinotomy close the laser coagulates. To further carry out the substitution performancesthe substances into the air with SF6 gas in a volume of 2 ml
Thus, when using the proposed method removes fibrosarcoma subretinal tissue is the basis of fibrovascular membranes low activity, replacing the defect pigment is on the epithelium of the affected area. This intervention allows for a constant eccentric fixation, reduce metamorphopsia that patients often report subjective improvement of vision. Partially restored the layer of retinal pigment epithelial blocks the possibility of relapse, taking barrier function.
The proposed method was tested in 8 patients with the wet form of age-related macular degeneration with formation of fibrovascular membranes low activity in the macular area of the Proposed method is illustrated by the following clinical example.
The patient Semenov, R. T., 1946 R.
Visual acuity of the right eye: 0,02 N. K. (2%) visual Acuity of the left eye: 0,9 N. K. Objectively right eye: the cornea is transparent, the front camera is average. The pupil is round, movable. The lens is transparent. The fundus of the eye. The optic disc pale pink outlined. In the macular region of fibrovascular membrane low-grade activity that generates the elevation of the retina. Optical coherence tomography: fibrovascular membrane height to 460 microns.
Diagnosis: Age-related macular degeneration, exudative, fibrovascular membrane low degree of activity.
Surgery: removal of fibrovascular membrane with autologous pigment epithelium.
The progress of the operation. Made of basal IRID Tome iris through the tunnel incision retinal scissors 250G. Of the flap is separated pigment epithelium of the iris and formed a plot differentage pigment epithelium 1 mm in diameter, which is placed in 0.2 ml of 0.85% NaCl. From the tube of material collected in a syringe with a volume of 1 ml. Formed suspension. Next, the patient received three port vitrectomy 25G, removed rear of the hyaloid membrane, formed retinotomy. Through retinotomy removed fibrovascular membrane. In the area of localization of the membrane through a needle introduced a cell suspension of the pigment epithelium of the iris. In the vitreal cavity entered performancesee connection, laser coagulation of the retina with subsequent replacement of the fluid in the vitreal cavity into the air and SF6 gas in a volume of 2 ml
The examination is made within 3 months after surgery. Visual acuity of the right eye: 0,07 N. K. (7%) visual Acuity of the left eye: 0,9 N. K. Objectively right eye: the cornea is transparent, the front camera is average. The pupil is round, movable. The lens is transparent. The fundus of the eye. The optic disc pale pink outlined. In the macular region of fibrovascular membrane low activity is absent. Optical coherence tomography: moderate degenerative changes of the retina. Subretinal neovascular membrane is absent.
A method of surgical treatment of fibrovascular membranes with a low degree of activity is involved in the macular region, including Subtotal vitrectomy, removal of fibrovascular membranes, tamponade of the retina performancesin connection with subsequent replacement by air and SF6 gas in a volume of 2 ml, endolasercoagulation of the retina, characterized in that the pre-spend iridotomy produce Department pigment layer with a diameter of 1 mm, and then preparing a suspension of 0.2 ml of 0.85% NaCl and the pigment layer, and the obtained suspension is injected at a location remote fibrovascular membrane before tamponade of the retina performancesin connection and endolasercoagulation.
SUBSTANCE: lachrymal prostaglandin E2 is measured before the implantation and on the 7-10th day following the implantation of a supplementary IOL. The pre- and post-operative prostaglandin concentrations are calculated. If the derived relation is 3.5-4 units, developing pigment dispersion syndrome is predicted.
EFFECT: method enables preventing developing pigment dispersion syndrome and pigment glaucoma in the given category of patients by the reliable prediction of the above syndrome in the early postoperative period.
SUBSTANCE: one month after a phacoemulsification of complicated cataract and an intracapsular implantation of an intraocular lens, 3-4 2mm notches are applied on the periphery of an anterior capsulorrhexis. That is followed by an YAG laser exposure at wave length 1,064 and power 1-2 mJ. If observing the preclinical signs of a contracture of a crystalline lens capsule, an ultrasonic biological microscopy is carried out to state if it is necessary to apply the notches.
EFFECT: method provides the more effective prevention of the above pathology by providing the reliable timely detection of the contracture of the capsular sac of the crystalline lens; the declared effect is selective and only covers the patients with the preclinical signs of the contracture as shown by the ultrasonic biological microscopy; it eliminated the capsular injuries caused by the effect of the surgical instruments and prevents the visual deterioration in the patients with concurrent conditions.
SUBSTANCE: two-staged laser exposure covers a trabecular region. The first stage involves incising the trabecula with a pulse neodymium YAG-laser at wavelength 1064 nm with pulses 6-36 mWt. The exposure is performed in a projection of one or more emissary veins until a Schlemm's canal starts bleeding. The second stage involves the exposure to a coagulation neodymium YAG-laser at wavelength 532 nm, spot diameter 50 mcm and exposure 0.2 sec. The trabecular tissue is coagulated along an inner wall of the Schlemm's canal until it corrugates along the full length of the trabecule in number of 90-120 coagulates.
EFFECT: fast intraocular pressure reduction, high hypotension effect and stable maintenance of intraocular pressure at the level of norm by de-blocking a fluid flow in the emissary veins and Schlemm's canal.
3 dwg, 3 ex
SUBSTANCE: invention refers to medicine, namely to ophthalmology, and can be used to prevent dehydration of a corneal flap accompanying LASIK procedure for various abnormal refractions. That is ensured by placing a microswab after the stage of corneal flap formation is completed from the flap inside. The microswab 6-7×2-3 mm is wetted with a balanced solution . The microswab is laid between two halves of the flap folded in half in parallel with its base.
EFFECT: method provides the adequate hydration of the corneal flap and its protection against the laser light in the environment of limited surgical field that in turn prevents formation of micro-edges, low-quality reduction and disturbed adaptation of the flap edges.
1 ex, 2 dwg
SUBSTANCE: invention refers to medicine, ophthalmology and aims at determining the indications for a laser coagulation required by myopia of various degrees in pregnant women. The method involves examining the eye ground and detecting retinal dystrophy. That is combined with the digital photographing of the eye ground in the first, second and third trimesters of pregnancy to determine an area and a volume of distribution of the macular pigment. If observing a decrease of these values in the second and third trimester as compared to the values of the first trimester by 10% and 8% and more respectively, the laser coagulation is recommended. If the values in the third trimester following the laser coagulation performed in the second trimester are equal to or less than the values of the second trimester, the repeated laser coagulation is recommended.
EFFECT: method provides the reliable screening control of the eye ground transition state, detecting the risk group of retinal dystrophy in pregnant women, enables detecting the early pathogenetically grounded preventive treatment, avoiding the eye contact, even in those cases when there are no clearly defined ophthalmological changes shown by conventional ophthalmological examination, thereby promotes reducing a rate of operative delivery, and increasing the number of spontaneous vaginal delivery.
SUBSTANCE: endoresection of an intraocular new growth is followed by covering the scleral bed surface with a photosensitising gel (PS gel) containing 0.1% monoethylene diamine monoamide chlorine adipate e6. The PS gel exposure makes 3 minutes. Thereafter, the scleral bed is exposed to laser light at a wave length of 662 nm, light dense of 60 J/cm2, with the fields of 4 mm in diameter in an air medium with the exposure covering the 1.5 mm surrounding tissues. The exposure is circle-wise from the periphery to the centre and covers the adjoining fields by 5% of the area.
EFFECT: avoiding the tumour cells remained viable on the scleral bed after the endoresection of the intraocular new growth, eliminating recurrences of tumours and metastases in the remote postoperative period.
SUBSTANCE: endoresection of an intraocular new growth is followed by covering the scleral bed surface with a photosensitising gel (PS gel) containing 0.1% monoethylene diamine monoamide chlorine adipate e6. The PS gel exposure makes 3 minutes. The residual gel is taken off. An active portion of one needle electrode is intraocularly applied on the scleral bed in parallel with the retinotomy border at 0.5-0.7 mm. The second electrode is applied in parallel to the first one at 3-4 mm to the centre of the scleral bed. That is followed by performing an electrochemical lysis (ECL) at the current intensity of 5 mA for 10 seconds. The electrodes are gradually moved along the scleral bed surface first circle-wise, in parallel to the retinotomy border, then from the periphery to the centre. The ECL covers the entire area of the scleral bed at the current intensity of 5 mA for 10-15 seconds in each position of the electrodes. That is followed by intraocular photodynamic therapy (PDT) along the entire area of the scleral bed with involving the 1.5 mm surrounding tissues. The patient is exposed to laser light at a wave length of 662 nm, power density of 60 J/cm2, by fields of 4 mm in diameter, circle-wise from the periphery to the centre, and involving the adjoining fields by 5% of the area.
EFFECT: avoiding the tumour cells remained viable on the scleral bed after the endoresection of the intraocular new growth, eliminating recurrences of tumours and metastases in the remote postoperative period.
SUBSTANCE: invention refers to medicine, namely to ophthalmology and can be used for determining indications for a repeated laser coagulation of retinal cysts. That is ensured by the retinal sonographic examination 3 months after the cyst coagulation. The cyst height and a base value are measured. The repeated coagulation is considered to be indicated if observing a decrease of the cyst and base sizes by less than 0.1 and 1 mm respectively.
EFFECT: method excludes unreasonable multiple recurrent sessions of laser coagulation by developing the determined criteria for the repeated laser exposure that in turn considerably reduces a risk of rough cicatrisation within the cyst, and a risk of an indirect macular injury.
SUBSTANCE: conjunctiva is incised. A rectangular superficial sclera flap is separated by 1/3 of a corneal thickness with its base to a limb until reaching transparent layers of a corneal stroma. A deep scleral flap is separated until reaching a scleral spur. The deep scleral flap is excised with an outer wall of a Shlemm's canal. Separating all the scleral flaps, excising the deep scleral flap with the outer wall of the Schlemm's canal and exposing a trabecule and a Descemet's membrane are performed with the use of an ultraviolet laser with a flat-section beam supplied to a surgical site by means of a light guide. A wave length is 308 nm, a pulse length is 10-20 ns, a frequency is 2-20 Hz, a power density is 300-800 mJ/cm2, a focal diameter is 0.2-1 mm.
EFFECT: method enables reducing the invasiveness and increasing the antihypertensive effect of the surgery by performing graduated and uniform incisions and scleral tissue separation, trabecule and Descemet's membrane ablation, reducing a risk of eye perforation and complications associated with inflammation and cicatrisation.
SUBSTANCE: invention refers to medicine and can be used in ophthalmology and ophthalmic oncology for the scleral bed treatment following endoresection of an intraocular new growth. After the endoresection of the intraocular new growth, electrodes are intraocularly applied on the surface of the scleral bed, and electrochemical lysis is performed. The electrodes are gradually moved along the entire area of the scleral bed. That is followed by intravitreal heat treatment covering the entire area of the scleral bed and surrounding tissues by 1.5 mm.
EFFECT: method enables avoiding an ability to preserve viable tumour cells on the scleral bed and in the sclera thickness, provides the absence of recurrent tumours and metastases in the remote postoperative period.
3 cl, 1 ex
SUBSTANCE: invention relates to medicine, in particular to ophthalmology, and is intended for treatment of refractive amblyopia in patients with high degree of myopia. Method includes surgical treatment excimer laser refractive operation Epi-LASIK. After operation, in case of complete epithelialisation, intravenous injections of ceraxon in dose 500 mg are made. Electrostimulation of retina and optic nerve are carried out simultaneously. Treatment is performed daily for 10 days.
EFFECT: method ensures high functional result and reduction of terms of visual rehabilitation in such patients, partially due to selected mode of impact of treatment components.
SUBSTANCE: invention relates to medicine, in particular to ophthalmology, and can be used for treatment of optic nerve atrophy of different etiology. Tree-component complex is implanted to patient in such a way that it covers optic nerve, posterior short ciliary arteries and part of retrobulbar cellular tissue, without joining them. Three-component complex contains mesenchymal stem cells, labeled with magnetic microparticles. Cells are transposed into biological or synthetic fine-porous material, which is tightly connected with polymer magnetic material with induction of constant magnetic field 1.5 mT, with multi-polar reversible magnetisation.
EFFECT: invention ensures improvement or stable stabilisation of visual functions, extension of vision field boundaries, acceleration of hemodynamics in retina and optic nerve.
SUBSTANCE: invention relates to medicine, namely to ophthalmology and aims at premaculyar hemorrhages in myopias of different severities in women with consecutive pregnancies. The posterior hyaloid is perforated using an YAG-laser at wavelength 1.064 nm. That is followed by the exposure to packaged pulse in a quasi-continuous operation. The posterior hyaloid is perforated by exposing to 1-4 three-pulse packages at pulse energy 0.03-0.1 mJ, while the formed hemophthalmia is lysed by 1-13 three-pulse packages at pulse energy 0.5-3 mJ. The exposure involves 1-5 sessions.
EFFECT: method ensures dose-sparing regimen of the laser exposure in treating the pregnant women by degrading laser pulse energy that prevents the risk of deterioration in the general somatic conditions and toxic effects on the patient and the foetus.
SUBSTANCE: invention refers to medicine, particularly ophthalmology, and concerns the laser treatment of primary open-angle glaucoma with a narrow anterior chamber angle. A single pulse laser (Nd-YAG laser) of power 1.5-2.5 mJ, pulse quantity 1-4 is used for iridectomy. That is followed by YAG laser trabecular activation. A trabecular zone is exposed within the anterior chamber angle at the level of Schlemm's canal to Nd-YAG laser light at wave length 1064 nm, power 1.6-2.0 mJ. A spot diameter is 10-15 mcm, a pulse quantity equispaced along the whole circular length is 55-70.
EFFECT: method enables increasing the anterior chamber angle in the patients suffering narrow-angle primary glaucoma and evacuating the extracellular fine deposits from the intertrabecular sheets by mechanical movement both of pigment, and other deposits in a trabecular zone to normalise intraocular pressure.
1 tbl, 2 ex
SUBSTANCE: invention refers to medicine, more specifically to ophthalmology, and may be used in laser cataract extraction with weak tendon of Zinn and vitreous hernia. A corneal approach to an anterior chamber is formed; a mydriatic and a viscoelastic are administered. A capsulorhexis is formed; an intracapsular ring is inserted, and a hydrodissection procedure follows. A nucleus of crystalline lens is removed with lens mass, and an intraocular lens is implanted. The nucleus of crystalline lens is destroyed using ND:YAG laser at wave length 1.44 mcm. Pulse length is 250 ms; power is 100 to 250 mJ; pulse repetition frequency is 10 to 30 Hz; emission power is 1 to 4 Wt; exposure time is 1 to 3 seconds. At the stage of the lens mass wash-out, vitreous cords are fixed in the vacuum mode of 150 mm Hg using an aspiration tip at the side of capsulorhexis. They are separated using ND:YAG laser at wave length 1.44 mcm, power 100 mJ, pulse length 250 ms, pulse repetition frequency 30 Hz, emission power 2 Wt, exposure time 2 seconds.
EFFECT: method provides the cataract extraction in a combination with the single-stage separation of single vitreous cords with reducing the intra- and postoperative complications, including shape deformation of the pupil and anterior lens capsule, and also preventing misalignment of the intraocular lens.
SUBSTANCE: group of inventions refers to medical equipment. A system comprises: a pulse laser light source with the laser light parameters specified to make a photodestruction corneal incision, a scanner for laser light travel, an electronic control unit, a modular unit for emitted laser pulse modulation. The control unit controls the scanner according to the incision geometry specified to form a flap and providing a border incision along a specific flap border and to cut out a flap bed according to a snake-like or spiral beam travel pattern with a number of opposite straight-line portions, and with a number of reverse curves each of which pieces the ends of the two straight-line portions and localised outside the flap. The control unit can also control the modular unit so that to suppress some laser pulses in the pattern sections localised outside the flap. According to the other version of the invention, the modular unit control provides for energy reduction and/or blanking of some laser pulses as approaching internal turns of the spiral pattern to ensure a fixed energy per a unit of area within the centre and at the periphery of the cornea.
EFFECT: using the presented group of inventions enables reducing the thermal injury of eye tissue when making the incisions by short-pulse laser light.
12 cl, 4 dwg
SUBSTANCE: invention refers to medical equipment. An apparatus comprises a contact surface adjoining an operated eye to be shaped; a first radiation source for generating a laser beam; optical components for directing the laser beam through the contact surface onto the eye; a depth metre for an anterior eye chamber adjoining the contact surface presenting the measurement data of the anterior eye chamber depth, at least in a single point; an electronic monitoring assembly connected to the metre and configured to state if the anterior eye chamber presented by the measurement data is less than at least one of the pre-set values, and to perform a provided action if the above depth is less than the pre-set value. The electronic monitoring assembly is provided to control at least one component to be monitored to terminate the supply of the contact surface to the eye, or to diverge them if the depth appeared to be less than the pre-set value.
EFFECT: using the given invention provides a high safety of the corneal endothelium injury.
10 cl, 1 dwg
FIELD: physics, optics.
SUBSTANCE: invention relates to optics. The weight-compensated mobile suspension of a focusing lens (12) of a laser system (10) comprises: a force generator for generating a force (G) which balances the weight of the focusing lens (12), a transmission mechanism which enables to apply a counteracting force (G) to the focusing lens (12) and enables compensating movement of the focusing lens upwards/downwards. The suspension also includes a device which guides movement of the focusing lens such that during compensating movement of the focusing lens (12) upwards/downwards, its optical axis (O) maintains at least its orientation and, preferably, its position in space.
EFFECT: during movement, the optical axis of the lens maintains at least its orientation and, preferably, its position in space.
9 cl, 1 dwg
SUBSTANCE: invention aims at an individual selection of laser energy options in transcleral diode laser cyclophotocoagulation (TDLC) in the patients suffering absolute painful glaucoma. A ciliary body thickness is measured by ultrasonic biological microscopy (UBM). If the ciliary body thickness is 0.54 mm or less, 6 laser applicates are marked through a circular arc of 90° in an upper section and through a circular arc of 90° in a lower section at power 1.2 Wt, pulse energy 3.6 J. If the ciliary body thickness is more than 0.54 mm, 8 laser applicates are marked through a circular arc of 135° in the upper section and through a circular arc of 135° in the lower section at power 1.8 Wt, pulse energy 5.4 J. The exposure in both cases are contact transcleral with using a diode laser in a continuous mode at wavelength 810 nm and exposure time 3.0 sec. The applicates are marked 1-2 mm from the limb and equally spaced from each other.
EFFECT: method provides a differential approach to selecting the laser energy options taking into account the condition of the ciliary body visualised by UBM which enables avoiding severe complications of TDLC, provides relieving pain syndrome, and reduces an initial intraocular tension.
SUBSTANCE: group of inventions refers to medicine. A material processing laser comprises a laser generating a pulsed laser radiation beam, measuring instruments for measuring power levels of a fundamental harmonic of the laser radiation beam and a power level of at least one higher harmonic derived by multiplying a laser radiation frequency, and an evaluation unit connected to the measuring instruments and configured to evaluate the laser radiation beam quality on the basis of the measured power level of the fundamental harmonic and on the basis of the measured power level of the laser radiation. A conversion efficiency measures the wave front quality and pulse duration generating the laser radiation beam.
EFFECT: calculating a ratio of the measured level of the higher harmonic to the measured power level of the fundamental harmonic enables evaluating the current frequency conversion effectiveness.
14 cl, 1 dwg