Variable frequency multifunctional middle infrared laser medical instrument with handle

Abstract

The application discloses a handle variable-frequency multifunctional middle infrared laser medical instrument, which comprises a fundamental frequency laser module, a water-cooling circulator, a near-infrared medical optical fiber, a multifunctional flexible optical cable and an integrated variable-frequency handle. The near-infrared fundamental frequency laser generated by the fundamental frequency laser module is coupled and received by the multifunctional flexible optical cable and transmitted to the integrated variable-frequency handle. The near-infrared fundamental frequency laser acts on a target position after being converted into target middle infrared medical laser by OPO variable-frequency in the integrated variable-frequency handle. Compared with the prior art, the handle variable-frequency multifunctional middle infrared laser medical instrument does not involve the use of complicated light guide arms and large transmission loss middle infrared optical fibers, can simultaneously realize the output of multiple key medical wavelength lasers, integrates the OPO variable-frequency device into a light integrated variable-frequency handle, greatly shortens the distance of the target middle infrared medical laser generated in the integrated variable-frequency handle and transmitted to the target position, improves the flexibility of the spatial multidimensional operation of the medical laser and reduces the transmission loss of the middle infrared medical laser.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser medical technology, and in particular to a handle variable-frequency multifunctional mid-infrared laser medical instrument. BACKGROUND

[0002] The mid-infrared spectral region (2.5 μm ~ 25 μm) covers the main spectral absorption peaks of various biological tissue components, making it highly interactive with biological tissues. Therefore, mid-infrared band lasers have important application value and broad application scenarios in the medical field. In terms of soft tissue laser ablation, the ablation lasers commonly used at present are mainly divided into ultraviolet lasers and infrared lasers. The ultraviolet laser has high single-photon energy and basically no collateral damage after ablation, but it has the risk of inducing tissue cell mutation. The mechanism of action of the infrared laser is to utilize the absorption of water molecules to specific laser wavelengths, and the water vaporizes and explodes during the ablation process, resulting in ablation or tissue inactivation, but there is a problem of relatively large collateral damage, which easily causes the degeneration of surrounding healthy tissues. The mid-infrared laser covers the strongest absorption peak of water molecules, and the water absorption coefficient is much larger than that of ultraviolet and infrared lasers, which has the significant advantage of fast ablation rate. Specifically, water molecules in biological tissues and hydroxyapatite calcium in tooth and bone tissues all have strong absorption to mid-infrared light with a wavelength in the range of 2.7 μm ~ 3.3 μm, which makes the laser with a wavelength in the range of 2.7 μm ~ 3.3 μm have unique advantages in the ablation of soft tissues such as skin and gums, and the cutting of hard tissues such as teeth and bones. At present, erbium lasers with wavelengths of 2.94 μm and 2.78 μm have been successfully used for the treatment of dental diseases. In particular, mid-infrared lasers with wavelengths in the range of 5.7 μm ~ 7.3 μm simultaneously target the dual absorption peaks of proteins and water. Based on the mechanism of the dual effects of protein structure denaturation and water absorption providing blasting force during the action, the lasers with wavelengths of 6.1 μm and 6.45 μm have much lower thermal damage energy threshold than other ablation wavelength lasers, have high ablation efficiency and minimal collateral damage, and related clinical studies show that the 6.45 μm laser has the characteristics of clear incision and small collateral damage (μm level) when used for tissue ablation, and has more advantages in surgical application scenarios with extremely high precision requirements such as neurosurgery, and has important application prospects in the field of precision medicine.

[0003] The existing mid-infrared laser generation technologies mainly include a direct stimulated radiation laser generation scheme and a fundamental frequency light nonlinear frequency conversion scheme. The direct laser generation scheme can output high-power laser in the 2.7 mu m ~ 3.3 mu m wave band, but due to the limitation of the laser gain medium, it is difficult to directly generate long-wave mid-infrared laser with a wavelength in the range of 5.7 mu m ~ 7.3 mu m and output short pulse laser required for medical treatment. The fundamental frequency light nonlinear frequency conversion scheme utilizes the nonlinear optical effect in the mid-infrared frequency conversion crystal, and can easily generate target medical laser with a wavelength that can be tuned in the 2.7 mu m ~ 3.3 mu m and 5.7 mu m ~ 7.3 mu m ranges, and the pulse width of the output mid-infrared laser can be as short as nanoseconds, picoseconds or even femtoseconds.

[0004] In the prior art, when the mid-infrared laser generated by the above technology is used for medical application, the mid-infrared laser needs to be coupled into an optical fiber or a mechanical light guide arm for transmitting the laser after being generated from the light source module. However, the flexible optical fiber made of sulfide and fluoride glass that can be used to transmit mid-infrared waveband laser has problems such as large absorption coefficient, obvious difference in absorption loss of different wavelengths of laser, low damage threshold, etc., and cannot meet the actual requirements of clinical medical treatment, especially the clinical application requirements of long-wave mid-infrared laser in the 5.7 mu m ~ 7.3 mu m wave band. Secondly, when using a mechanical light guide arm for transmission, the 5.7 mu m ~ 7.3 mu m waveband mid-infrared medical laser is easily absorbed and lost by water vapor in the long-distance light guide arm, and the mechanical light guide arm structure is complex and not flexible. The above problems greatly limit the promotion of mid-infrared medical laser in clinical application, especially the clinical application promotion of 5.7 mu m ~ 7.3 mu m waveband mid-infrared medical laser. SUMMARY

[0005] The purpose of the present application is to provide a handle frequency conversion type multifunctional mid-infrared laser medical instrument, which aims to overcome the problems of low transmission loss and poor operability of the existing mid-infrared laser application technology when transmitting 2.7 mu m ~ 3.3 mu m waveband and 5.7 mu m ~ 7.3 mu m waveband mid-infrared medical laser to the target position.

[0006] The present application provides a handle frequency conversion type multifunctional mid-infrared laser medical instrument, which comprises a fundamental frequency laser module, a water-cooled circulator, a near-infrared medical optical fiber, a multifunctional flexible optical cable and an integrated frequency conversion handle.

[0007] The base frequency laser module comprises a base frequency light source, a first laser control assembly, a first coupling assembly and a second coupling assembly, the base frequency light source is used for generating near-infrared base frequency laser, the first laser control assembly is used for controlling and splitting the near-infrared base frequency laser to form first base frequency laser and second base frequency laser, and the first coupling assembly and the second coupling assembly are used for coupling the first base frequency laser and the second base frequency laser into the near-infrared medical optical fiber and the multifunctional flexible optical cable respectively;

[0008] The multifunctional flexible optical cable connects the base frequency laser module and the integrated frequency conversion handle, and comprises a near-infrared energy transmission quartz optical fiber, a water inlet pipe and a water return pipe which are arranged in the outer sheath and are spaced apart; the near-infrared energy transmission quartz optical fiber is used for receiving the second base frequency laser coupled by the coupling assembly and transmitting the second base frequency laser to the integrated frequency conversion handle; the water inlet pipe and the water return pipe are connected to the water-cooled circulator and are used for conveying cooling water to water-cool and dissipate heat for the integrated frequency conversion handle.

[0009] The integrated frequency conversion handle comprises an integrated shell, an output window and a collimating lens, an input cavity, a mid-infrared frequency conversion crystal, an output cavity and a second laser control assembly which are arranged in the integrated shell and are sequentially arranged along a transmission light path; two ends of the integrated shell are fixed with the multifunctional flexible optical cable and the output window respectively; the second base frequency laser emitted from the multifunctional flexible optical cable is collimated by the collimating lens and then vertically enters an optical parametric oscillator composed of the input cavity, the mid-infrared nonlinear crystal and the output cavity; the second base frequency laser is converted into signal light, idler light and residual base frequency laser after passing through the optical parametric oscillator; the output cavity selects and outputs the signal light in the 2.7 μm-3.3 μm band and the idler light in the 2.7 μm-3.3 μm band or the 5.7 μm-7.3 μm band as target mid-infrared medical laser; and the target mid-infrared medical laser is focused, shaped and attenuated by the second laser control assembly and then is output from the output window.

[0010] According to one embodiment of the present application, the integrated frequency conversion handle further comprises a water channel, a crystal heat sink, a beam combiner, an indicator light source and a base frequency light eliminator which are arranged in the integrated shell;

[0011] The water channel is connected with the water inlet pipe and the water return pipe;

[0012] The crystal heat sink is arranged around the mid-infrared frequency conversion crystal and is connected with the water channel, and is used for dissipating heat for the mid-infrared frequency conversion crystal;

[0013] The indicator light source is used for generating visible indicator light;

[0014] The beam combiner is arranged on the light output side of the output mirror, and is used for separating the residual fundamental laser from the target mid-infrared medical laser and combining the indicating light with the target mid-infrared medical laser into one beam.

[0015] The fundamental light absorber is connected with the water channel, and is used for receiving the residual fundamental laser.

[0016] According to an embodiment of the present application, the second laser control assembly comprises a first lens and a second lens arranged on the light path of the optical parametric oscillator, and a translation stage fixed on an integrated housing.

[0017] One of the first lens and the second lens is fixed in the integrated housing, and the other is fixed on the translation stage. By controlling the movement of the translation stage, the distance between the first lens and the second lens can be adjusted, so as to adjust the position and size of the focal spot of the target mid-infrared medical laser.

[0018] According to an embodiment of the present application, the multifunctional flexible optical cable further comprises a first connector and a second connector arranged at two ends, and a reinforcing core and a cable control line arranged in the outer sheath and spaced apart from the near-infrared energy transmission quartz optical fiber, the water inlet pipe and the water return pipe. The inner sides of the first connector and the second connector are connected with the outer sheath and the reinforcing core, and the outer sides are respectively fixed with the output end of the fundamental laser module and the input end of the integrated frequency conversion handle, so as to strip and fix the near-infrared energy transmission quartz optical fiber, the water inlet pipe, the water return pipe and the cable control line one by one.

[0019] According to an embodiment of the present application, the input mirror is coated with a dielectric film which is highly transparent to the second fundamental laser and highly reflective to signal light and idler light. The output mirror is coated with a dielectric film which is highly transparent to the second fundamental laser, has a reflectivity greater than 40% to signal light, and has a transmittance greater than 40% to idler light in the 2.7 μm~3.3 μm wave band or the 5.7 μm~7.3 μm wave band.

[0020] According to an embodiment of the present application, the output mirror comprises a movable first region, a second region and a third region.

[0021] The first region is highly reflective to signal light in the 2.7 μm~3.3 μm wave band, and has a transmittance greater than 40% to idler light in the 5.7 μm~7.3 μm wave band.

[0022] The second region has a transmittance greater than 40% to signal light in the 2.7 μm~3.2 μm wave band, and is highly reflective to idler light in the 5.7 μm~7.3 μm wave band.

[0023] The third region has a transmittance of greater than 40% for signal light in a wavelength range of 2.7 to 3.3 microns, and a transmittance of greater than 40% for idler light in a wavelength range of 2.7 to 3.3 microns and 5.7 to 7.3 microns.

[0024] According to an embodiment of the present application, the near-infrared fundamental laser has a wavelength range of 0.8 to 2.5 microns, a single pulse energy greater than 0.1 mJ, a pulse repetition frequency of 1 Hz to 200 kHz, and a pulse width of 0.1 to 1000 ns.

[0025] According to an embodiment of the present application, the first laser control assembly includes a polarization beamsplitter, a rotating stage, and a half-wave plate disposed on the rotating stage. The near-infrared fundamental laser is polarized by the half-wave plate and then incident on the polarization beamsplitter to form the first fundamental laser and the second fundamental laser. The rotating stage is used to adjust the angle of the half-wave plate to control the energy ratio of the first fundamental laser and the second fundamental laser.

[0026] According to an embodiment of the present application, the integrated frequency conversion handle further includes an end light guide needle connected to one end of the integrated frequency conversion handle near the output window, and internally provided with a reflection adjustment lens of the target mid-infrared medical laser for adjusting the light output direction of the target mid-infrared medical laser.

[0027] According to an embodiment of the present application, the laser power supply, the display control panel, and the integrated cabinet are further included. The fundamental laser module, the laser power supply, and the water-cooled circulator are integrated into the integrated cabinet. The control panel is installed on the outside of the shell of the integrated cabinet. The water-cooled circulator is used for water-cooled heat dissipation of the fundamental laser module and the integrated frequency conversion handle. The display control panel is electrically connected with the fundamental laser module, the laser power supply, and the water-cooled circulator, and is used to provide selection of medical laser parameters such as output power, repetition frequency, and cooling water temperature.

[0028] The application provides a handle variable frequency type multifunctional middle infrared laser medical instrument, which separates an integrated variable frequency handle for generating middle infrared medical laser and a basic frequency laser module for generating near infrared laser in space, adopts a multifunctional flexible optical cable including a near infrared energy transmission quartz optical fiber to firstly transmit the basic frequency laser to the integrated variable frequency handle close to a target position, and then generates middle infrared medical laser in the integrated variable frequency handle close to the target position, and since the near infrared laser adopts the near infrared quartz optical fiber transmission which has low transmission loss, is very mature in manufacturing and has high laser damage threshold, the overall energy transmission efficiency of the laser transmission to the vicinity of the target position is high. The integrated variable frequency handle design integrates the middle infrared optical parametric oscillator in the light and compact integrated variable frequency handle, and the target middle infrared medical laser in the 2.7-3.3 mu m band and the 5.7-7.3 mu m band can be directly applied to the target position, avoiding long distance transmission of the target middle infrared medical laser in the optical fiber or mechanical light guide arm. Compared with the prior art, the handle variable frequency type multifunctional middle infrared laser medical instrument shortens the distance of the target middle infrared medical laser transmission to the target position, reduces the medical laser transmission loss and improves the spatial multi-dimensional operation flexibility of the medical laser.

[0029] Meanwhile, the handle variable frequency type multifunctional middle infrared laser medical instrument can simultaneously provide near infrared basic frequency laser, target middle infrared medical laser in the 2.7-3.3 mu m band and / or the 5.7-7.3 mu m band and other multi-band medical laser outputs, can be used for surgical treatment of multiple departments and multiple diseases, has the integrated processing capability of soft and hard tissues, meets the needs of interventional and non-interventional surgery, widens the range of laser indications, and is a multifunctional handle variable frequency type multifunctional middle infrared laser medical instrument. BRIEF DESCRIPTION OF DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative effort.

[0031] Figure 1 A structure schematic view of a handle variable frequency type multifunctional middle infrared laser medical instrument provided by the embodiment of the application;

[0032] Figure 2 A cross-sectional schematic view of a multifunctional flexible optical cable provided by the embodiment of the application;

[0033] Figure 3 A plane structure schematic view of a basic frequency laser module provided by the embodiment of the application;

[0034] Figure 4 A planar structure schematic diagram of an integrated variable-frequency handle provided by the embodiment of the present application. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the embodiment of the present application clearer, the technical scheme of the embodiment of the present application will be described clearly and completely below with reference to the drawings in the embodiment of the present application. Obviously, the described embodiment is a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiment in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0036] In the following detailed description, many specific details are proposed in order to provide a comprehensive understanding of the present application. However, it is obvious for those skilled in the art that the present application can be implemented without some of the specific details. The following description of the embodiments is only for the purpose of providing a better understanding of the present application by showing examples of the present application.

[0037] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0038] The high transmission in the present application refers to a transmittance greater than 90%, and the high reflection refers to a reflectance greater than 95%.

[0039] The near-infrared in the present application refers to a laser wavelength in the range of 0.7 μm~2.5 μm, and the mid-infrared refers to a laser wavelength in the range of 2.5 μm~12 μm.

[0040] The present application provides a handle variable-frequency multifunctional mid-infrared laser medical instrument, which is shown in Figures 1 to 4 , and Figure 1 A structure schematic diagram of a handle variable-frequency multifunctional mid-infrared laser medical instrument provided by the embodiment of the present application; Figure 2 A planar structure schematic diagram of a fundamental laser module provided by the embodiment of the present application; Figure 3 A cross section of a multifunctional flexible optical cable provided by the embodiment of the present application; Figure 4 A planar structure schematic diagram of an integrated variable-frequency handle provided by the embodiment of the present application.

[0041] Referring to Figure 1 , the handle variable-frequency multifunctional mid-infrared laser medical instrument of the embodiment of the present application comprises a fundamental laser module 1, a water-cooled circulator 2, a near-infrared medical optical fiber 3, a multifunctional flexible optical cable 4 and an integrated variable-frequency handle 5.

[0042] The fundamental frequency laser module 1 includes a fundamental frequency light source 11, a first laser control component 12, a first coupling component 13 and a second coupling component 14. The fundamental frequency light source 11 is used to generate and output near-infrared fundamental frequency laser. The first laser control component 12 is used to control and split the near-infrared fundamental frequency laser to form a first fundamental frequency laser and a second fundamental frequency laser. The first coupling component 13 and the second coupling component 14 are respectively used to couple the first fundamental frequency laser and the second fundamental frequency laser into the near-infrared medical optical fiber 3 and the multifunctional flexible optical cable 4.

[0043] The first laser control component 12 is used to perform spot shaping on the near-infrared fundamental frequency laser light output by the fundamental frequency light source 11, providing a suitable spot size and beam divergence angle for the subsequent first coupling component 13 and second coupling component 14. The first laser control component 12 performs polarization state control and beam splitting on the near-infrared fundamental frequency laser light to achieve a controllable energy ratio between the first and second fundamental frequency laser light. The first fundamental frequency laser light formed after the beam splitting is coupled out and used for near-infrared laser interventional ablation procedures such as medical laser stone fragmentation and liver tumor resection. The second fundamental frequency laser light formed is coupled out and used as the pump laser for the target mid-infrared medical laser generated in the subsequent integrated frequency conversion handle.

[0044] Near-infrared medical optical fiber 3 is connected to the output end of fundamental frequency laser module 1 and is used to transmit the first fundamental frequency laser. Near-infrared medical optical fiber 3 is made of quartz glass. Generally, quartz glass absorbs near-infrared laser light of specific wavelengths due to the presence of hydroxyl groups (OH) in quartz glass. Therefore, to minimize losses during near-infrared laser transmission, near-infrared medical optical fiber 3 is preferably made of OH-free quartz glass. The core size of near-infrared medical optical fiber 3 must be customized based on clinical application requirements.

[0045] The multifunctional flexible optical cable 4 connects the baseband laser module 1 and the integrated frequency conversion handle 5. Figure 2As shown, the multifunctional flexible optical cable 4 includes the near-infrared energy-carrying quartz optical fiber 41, the water inlet pipe 42, and the water return pipe 43, which are covered in the outer sheath 44 and are arranged at intervals. The near-infrared energy-carrying quartz optical fiber 41 is used to receive the second fundamental frequency laser coupled by the second coupling assembly 14 and transmit the second fundamental frequency laser to the integrated frequency conversion handle 5. To ensure flexibility, the cross section of the multifunctional flexible optical cable 4 is preferably circular, the transverse cross-sectional diameter is less than 10 mm, and the bendable curvature diameter of the near-infrared energy-carrying quartz optical fiber 41 is less than 10 cm. In order to improve the efficiency of the second fundamental frequency laser coupled into the near-infrared energy-carrying quartz optical fiber 41, the end face of the near-infrared energy-carrying quartz optical fiber 41 should be kept clean and placed near the focal point of the second fundamental frequency laser beam focused by the second coupling assembly 14. The material of the near-infrared energy-carrying quartz optical fiber 41 is quartz glass, preferably OH-free quartz glass optical fiber. In order to avoid damage to the near-infrared energy-carrying quartz optical fiber 41 due to the high power density of the second fundamental frequency laser, the near-infrared medical optical fiber preferably uses a large-core multimode quartz optical fiber with a core diameter of 100 μm to 500 μm. The water inlet pipe 42 and the water return pipe 43 are connected to the water-cooled circulator 2 and are used to transport cooling water to cool and dissipate heat for the integrated frequency conversion handle 5. The water inlet pipe 42, the water return pipe 43, and the outer sheath 44 are made of flexible high-strength materials, so the multifunctional flexible optical cable 4 has the ability to bend and can withstand high-strength stress. The size of the water inlet pipe 42 and the water return pipe 43 can be determined according to the maximum cooling flux required by the integrated frequency conversion handle 5. In order to prevent deformation of the multifunctional flexible optical cable 4 caused by long-term use, the internal empty space of the outer sheath of the multifunctional flexible optical cable 4 can be filled with flexible plastic filler.

[0046] As Figure 3As shown, the integrated frequency conversion handle 5 comprises an integrated housing 501, an output window 502, and a collimating lens 503, an input cavity mirror 504, a mid-infrared frequency conversion crystal 505, an output cavity mirror 506, and a second laser control assembly 507 arranged in the integrated housing 501 along the transmission light path. The two ends of the integrated housing are fixed with the multifunctional flexible optical cable and the output window. The second fundamental frequency laser emitted from the multifunctional flexible optical cable 4 is collimated by the collimating lens 503 and then vertically enters the optical parametric oscillator (OPO) composed of the input cavity mirror 504, the mid-infrared nonlinear crystal 505, and the output cavity mirror 506. The second fundamental frequency laser is converted into signal light, idler light, and residual fundamental frequency laser after passing through the optical parametric oscillator (OPO). In order to ensure the frequency conversion efficiency of the optical parametric oscillator, the input cavity mirror 504 and the output cavity mirror 506 should be placed vertically to the second fundamental frequency laser collimated by the collimating lens 503. When the end face of the mid-infrared frequency conversion crystal 505 is placed vertically to the second fundamental frequency laser, the phase matching angle of the mid-infrared frequency conversion crystal corresponds to the idler light output wavelength in the 5.7-7.3 μm band. The output cavity mirror 506 selects and outputs the signal light in the 2.7-3.3 μm band and the idler light in the 2.7-3.3 μm band or the 5.7-7.3 μm band as the target mid-infrared medical laser. The target mid-infrared medical laser is focused, shaped, and attenuated by the second laser control assembly 507 and then output from the output window. In order to reduce the loss of the second fundamental frequency laser and lower the light output threshold of the optical parametric oscillator, the end face of the mid-infrared frequency conversion crystal 505 is coated with a high-transmission film for the second fundamental frequency laser, signal light, and idler light. The input cavity mirror 504 and the output cavity mirror 506 should be arranged as close to the end face of the mid-infrared frequency conversion crystal 505 as possible. In order to make the integrated frequency conversion handle compact, stable, and reliable, the collimating lens 503, the input cavity mirror 504, the mid-infrared frequency conversion crystal 505, and the output cavity mirror 506 are fixed by an integrated fixed mirror frame. The light transmission diameter of the integrated fixed mirror frame is less than 15 mm.

[0047] In the present application, the first fundamental frequency laser is output from the near-infrared medical optical fiber 3 for near-infrared laser interventional ablation such as medical laser lithotripsy and liver tumor resection. The second fundamental frequency laser is transmitted to the integrated frequency conversion handle 5 through the multifunctional flexible optical cable 4. Then, the target mid-infrared medical laser is efficiently generated by OPO frequency conversion in the integrated frequency conversion handle 5. The target mid-infrared medical laser can directly act on the target position after being output from the integrated frequency conversion handle 5.

[0048] The application provides a handle variable frequency type multifunctional middle infrared laser medical instrument, which separates an integrated variable frequency handle for generating middle infrared medical laser and a basic frequency laser module for generating near infrared laser in space, adopts a multifunctional flexible cable including a near infrared energy transmission quartz optical fiber to first transmit the basic frequency laser to the integrated variable frequency handle close to a target position, and then generates middle infrared medical laser by variable frequency in the integrated variable frequency handle close to the target position. Since the near infrared laser adopts a near infrared quartz optical fiber transmission with low transmission loss, very mature manufacturing and high laser damage threshold, the overall energy transmission efficiency of the laser transmission to the vicinity of the target position is high. The integrated variable frequency handle design integrates the middle infrared optical parametric oscillator in the light and compact integrated variable frequency handle, generates target middle infrared medical laser in the 2.7 μm-3.3 μm band and the 5.7 μm-7.3 μm band in the integrated variable frequency handle, and directly acts on the target position, avoiding long distance transmission of the target middle infrared medical laser in the optical fiber or the mechanical light guide arm. Compared with the prior art, the handle variable frequency type multifunctional middle infrared laser medical instrument shortens the distance of the target middle infrared medical laser transmission to the target position, reduces the medical laser transmission loss and improves the spatial multi-dimensional operation flexibility of the medical laser.

[0049] Meanwhile, the handle variable frequency type multifunctional middle infrared laser medical instrument can simultaneously provide near infrared basic frequency laser, target middle infrared medical laser in the 2.7 μm-3.3 μm band and / or the 5.7 μm-7.3 μm band and other multi-band medical laser outputs, can be used for surgical treatment of multiple departments and multiple diseases, has the ability of soft and hard tissue integrated processing, meets the needs of interventional and non-interventional surgery, widens the range of laser indications, and is a multifunctional handle variable frequency type multifunctional middle infrared laser medical instrument.

[0050] In some embodiments, as Figure 3As shown, the integrated frequency conversion handle 5 further comprises a water channel 508, a crystal heat sink 509, a beam combiner 510, an indicator light source 511 and a fundamental light eliminator 512 arranged in the integrated housing 501. The water channel 508 is connected with the water inlet pipe 42 and the water return pipe 43. The crystal heat sink 509 is arranged around the side of the mid-infrared frequency conversion crystal 505 and connected with the water channel 508 for heat dissipation of the mid-infrared frequency conversion crystal 505. Cooling and temperature control of the mid-infrared frequency conversion crystal 505 can improve the power and wavelength stability of the target mid-infrared medical laser generated by the optical parametric oscillator, and avoid damage caused by heat accumulation of the mid-infrared frequency conversion crystal 505. The beam combiner 510 is arranged on the light output side of the output cavity mirror 506, for separating the residual fundamental laser from the target mid-infrared medical laser and combining the visible indicator light generated by the indicator light source 511 with the target mid-infrared medical laser into one beam. The function of the beam combiner 510 can be realized by coating. Generally, after coating, the beam combiner 510 has high reflectivity to the residual pump laser, high transmissivity to the signal light and idler light, and the reflected residual pump laser is incident to the fundamental light eliminator 512. The fundamental light eliminator 512 is connected with the water channel 508 for receiving the residual fundamental laser, and the waste heat generated by the residual fundamental laser is taken away by the cooling water flowing in the water channel 508.

[0051] In some embodiments, as shown in FIG. 1, the integrated frequency conversion handle 5 further comprises a second laser control assembly 507 arranged in the integrated housing 501. The second laser control assembly 507 comprises a first lens 507-1 and a second lens 507-2 arranged on the output light path of the optical parametric oscillator, and a translation stage 507-3 fixed on the integrated housing 501. One of the first lens 507-1 and the second lens 507-2 is fixed in the integrated housing 501, and the other is fixed on the translation stage 507-3. By controlling the movement of the translation stage 507-3, the distance between the first lens 507-1 and the second lens 507-2 can be adjusted, so as to adjust the focal spot position and size of the target mid-infrared medical laser. Figure 3 In some embodiments, as shown in FIG. 1, the integrated frequency conversion handle 5 further comprises a second laser control assembly 507 arranged in the integrated housing 501. The second laser control assembly 507 comprises a first lens 507-1 and a second lens 507-2 arranged on the output light path of the optical parametric oscillator, and a translation stage 507-3 fixed on the integrated housing 501. One of the first lens 507-1 and the second lens 507-2 is fixed in the integrated housing 501, and the other is fixed on the translation stage 507-3. By controlling the movement of the translation stage 507-3, the distance between the first lens 507-1 and the second lens 507-2 can be adjusted, so as to adjust the focal spot position and size of the target mid-infrared medical laser.

[0052] In some embodiments, as shown in FIG. 1, the integrated frequency conversion handle 5 further comprises a second laser control assembly 507 arranged in the integrated housing 501. The second laser control assembly 507 comprises a first lens 507-1 and a second lens 507-2 arranged on the output light path of the optical parametric oscillator, and a translation stage 507-3 fixed on the integrated housing 501. One of the first lens 507-1 and the second lens 507-2 is fixed in the integrated housing 501, and the other is fixed on the translation stage 507-3. By controlling the movement of the translation stage 507-3, the distance between the first lens 507-1 and the second lens 507-2 can be adjusted, so as to adjust the focal spot position and size of the target mid-infrared medical laser. Figure 2As shown, the multifunctional flexible optical cable 4 further comprises a first connector and a second connector disposed at both ends, a reinforcing core 45 and a cable control line 46 disposed in the outer sheath 44 and spaced apart from the near-infrared energy transmission quartz optical fiber, the water inlet pipe, and the water return pipe. The inner side of the first connector and the second connector is connected with the outer sheath 44 and the reinforcing core 45, and the outer side is fixed with the output end of the base frequency laser module 1 and the input end of the integrated frequency conversion handle 5, respectively, for stripping and fixing the near-infrared energy transmission quartz optical fiber 41, the water inlet pipe 42, the water return pipe 43, and the cable control line 46 one by one. The reinforcing core 45 is used to enhance the bending stress of the multifunctional flexible optical cable 4, and is usually made of metal or alloy with good elasticity and toughness. When the multifunctional flexible optical cable 4 is bent, the anti-bending stress is generated inside the reinforcing core 45, which makes the multifunctional flexible optical cable 4 have a greater bending curvature when it is bent, preventing the multifunctional flexible optical cable 4 from being excessively bent and causing the transmission efficiency of the near-infrared energy transmission quartz optical fiber 41 to decrease. The cable control line 46 is used to control the electrical devices in the integrated frequency conversion handle 5 and transmit control signals.

[0053] In some preferred embodiments, the material of the near-infrared energy transmission quartz optical fiber 41 adopts OH-free quartz glass. The absorption of the quartz optical fiber of this material to the laser with a wavelength near 2 μm is much lower than that of general quartz optical fiber, which reduces the loss during laser transmission and increases the damage threshold.

[0054] In some preferred embodiments, the near-infrared energy transmission quartz optical fiber 41 adopts a polarization maintaining optical fiber. The second base frequency laser requires linearly polarized light in the nonlinear frequency conversion process, so the near-infrared energy transmission quartz optical fiber 41 should try to ensure that the polarization direction does not change when transmitting the second base frequency laser.

[0055] In some embodiments, the input mirror is coated with a dielectric film that is highly transmissive to the second base frequency laser and highly reflective to signal light and idler light; the output mirror is coated with a dielectric film that is highly transmissive to the second base frequency laser, has a reflectivity greater than 40% to signal light, and has a transmittance greater than 40% to idler light in the 2.7 μm~3.3 μm waveband or the 5.7 μm~7.3 μm waveband.

[0056] In some embodiments, the output cavity mirror 506 includes a movable first region, a second region, and a third region. In this embodiment, there is no restriction on the arrangement and distribution of the first region, the second region, and the third region. The first region has high reflection for signal light in the 2.7μm~3.3μm band, and a transmittance of idle light in the 5.7μm~7.3μm band is greater than 40%. The second region has a transmittance of signal light in the 2.7μm~3.2μm band is greater than 40%, and high reflection for idle light in the 5.7μm~7.3μm band. The third region has a transmittance of signal light in the 2.7μm~3.3μm band is greater than 40%, and a transmittance of idle light in the 2.7μm~3.3μm band and the 5.7μm~7.3μm band is greater than 40%. In one specific embodiment, when the output cavity mirror 506 is rotated so that the first region, the end face of the mid-infrared frequency-converting crystal 804, and the input cavity mirror 803 form a single-resonance optical parametric oscillator for signal light (3μm laser), the first region selects the second fundamental laser, signal light, and idler light to output only idler light in the 5.7μm to 7.3μm band. Similarly, the second region selects to output signal light in the 2.7μm to 3.3μm band. The third region selects to simultaneously output signal light in the 2.7μm to 3.3μm band and idler light in the 5.7μm to 7.3μm band. By switching the three different regions of the output cavity mirror, wavelength selection of the target mid-infrared medical laser can be achieved.

[0057] In some embodiments, as Figure 4 As shown, the first laser control component 12 includes a polarization beam splitter 125, a rotating stage (not shown), and a half-wave plate 124 disposed on the rotating stage. After the near-infrared fundamental frequency laser is polarized by the half-wave plate 124, it is incident on the polarization beam splitter 125 to form a first fundamental frequency laser and a second fundamental frequency laser. The polarization directions of the first fundamental frequency laser and the second fundamental frequency laser are orthogonal. The rotating stage is used to adjust the angle of the half-wave plate 124 to control the energy ratio of the first fundamental frequency laser and the second fundamental frequency laser, thereby controlling the laser energy ratio output from the near-infrared medical optical fiber 3 and the multifunctional flexible optical cable 4. The polarization beam splitter 125 commonly uses an incident angle of 45° or 56°. In order to facilitate optical path adjustment, 45° is preferably used.

[0058] In some embodiments, the first laser control assembly 12 further comprises a first turning mirror 121, a first lens 122, and a second lens 123. The first turning mirror 121 is used to adjust and optimize the transmission direction of the near-infrared fundamental laser emitted by the fundamental light source 11, so that the near-infrared fundamental laser is vertically incident on the first lens 122. The first lens 122 and the second lens 123 constitute a telescope shaping system for collimating, expanding or shrinking the near-infrared fundamental laser. The focal length is determined according to the required spot size in the subsequent coupling, and the distance between the two lenses is about the sum of the focal lengths. When the first lens 122 and the second lens 123 are both convex lenses, there is a real focal point between them, and the shaping distance is relatively long. When one of the first lens 122 and the second lens 123 is a concave lens and the other is a convex lens, there is no real focal point between them, and the shaping distance is relatively short.

[0059] In some embodiments, as shown in FIG. 1, the first coupling assembly 13 comprises a second turning mirror 131, a third turning mirror 132, a first coupling lens 133, and a first coupling adjustment frame 134. The first fundamental laser is adjusted in transmission direction by the second turning mirror 131 and the third turning mirror 132, and then is vertically incident on the first coupling lens 133. The first coupling lens 133 converts the mode spot size of the incident first fundamental laser to the mode spot size of the near-infrared medical optical fiber 3, so as to facilitate fiber coupling. The first coupling adjustment frame 134 is used to fix and adjust the center position and the pitch angle of the near-infrared medical optical fiber 3, so as to optimize the coupling efficiency of the near-infrared medical optical fiber 3. Figure 4 The second coupling assembly 14 comprises a fourth turning mirror 141, a second coupling lens 142, and a second coupling adjustment frame 143. The second fundamental laser is adjusted in transmission direction by the fourth turning mirror 141, and then is vertically incident on the second coupling lens 142. The second coupling lens 142 converts the mode spot size of the incident second fundamental laser to the mode spot size of the near-infrared energy transmission quartz optical fiber 41. The fourth turning mirror 141 is used to adjust the transmission direction of the second fundamental laser so that it is vertically incident on the second coupling lens 142. The second coupling adjustment frame 143 is placed near the focal point position behind the second coupling lens 142, and is used to fix and adjust the center position and the pitch angle of the near-infrared energy transmission quartz optical fiber 41, so as to optimize the coupling efficiency of the near-infrared energy transmission quartz optical fiber 41.

[0060] In some embodiments, the near-infrared fundamental laser output by the fundamental light source 11 is a nanosecond pulsed laser with a wavelength in the range of 1.9 μm to 2.2 μm. Specifically, the pulse energy is greater than 0.2 mJ, the pulse repetition frequency is 1 Hz-20 kHz, and the pulse width is less than 200 ns.

[0061] In some preferred embodiments, the fundamental light source 11 is an actively Q-switched solid-state pulsed laser with an output wavelength in the range of 1.9 μm to 2.2 μm. Specifically, including but not limited to Tm:YLF laser with an emission wavelength of 1.91 μm, Tm:YAP laser with an emission wavelength of 1.94 μm to 2.1 μm, Tm:YAG laser with an emission wavelength of 2.02 μm, Ho:YAG laser with an emission wavelength of 2.09 μm, Ho:YLF laser with an emission wavelength of 2.05 μm, Tm, Ho:YAG laser with an emission wavelength of 2.09 μm.

[0062] In some embodiments, both the input mirror 504 and the output mirror 506 are made of a material with a laser damage threshold higher than 500 MW / cm^2 and an absorption coefficient for mid-infrared light less than 0.05 cm^(-1). Specifically, including but not limited to ZnSe, Si, CaF2, ZnS, Ge, HRSi, etc.

[0063] In some embodiments, the mid-infrared frequency conversion crystal 505 is a nonlinear crystal with an effective nonlinear coefficient greater than 10 pm / V and a transmission range covering 1.9 μm to 8 μm. Specifically, including but not limited to ZnGeP2, BaGa4Se7, AgGaSe2, BaGa2GeSe6, AgGaSe2, etc.

[0064] In some embodiments, the handle frequency conversion type multifunctional mid-infrared laser medical instrument further comprises a terminal light guide needle 6 connected to one end of the output window of the integrated frequency conversion handle 5, and internally provided with a target mid-infrared medical laser reflection adjusting lens for further adjusting the light output direction of the target mid-infrared medical laser guided to the affected area, further enhancing the spatial operation flexibility and functional diversity.

[0065] In some embodiments, the handle frequency conversion type multifunctional mid-infrared laser medical instrument further comprises a laser power supply 7, a display control panel 8, and an integrated cabinet 9. The fundamental laser module 1, the water cooling circulator 2, and the laser power supply 7 are integrated into the integrated cabinet 9, the control panel 8 is installed on the outside of the shell of the integrated cabinet 9, and the water cooling circulator 2 is connected to the water inlet pipe 42 and the water return pipe 43 of the multifunctional flexible optical cable 4, while cooling the fundamental light source 11 and the integrated frequency conversion handle 5. The display control panel 4 is directly electrically connected to the fundamental laser module 1, the water cooling circulator 2, and the laser power supply 7, and is connected to the integrated frequency conversion handle 5 through the multifunctional flexible optical cable 4, for providing selection of medical laser parameters such as output power, repetition frequency, and cooling water temperature.

[0066] The above merely illustrates the specific embodiments of the present application, but the protection scope of the present application is not limited thereto, and any skilled person in the art can easily think of various equivalent modifications or replacements within the technical range disclosed by the present application, and these modifications or replacements shall be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A multifunctional mid-infrared laser medical instrument with a frequency conversion function, characterized in that: include: Fundamental frequency laser module, water-cooled circulator, near-infrared medical optical fiber, multifunctional flexible optical cable, integrated frequency conversion handle; The fundamental frequency laser module includes a fundamental frequency light source, a first laser control component, a first coupling component, and a second coupling component. The fundamental frequency light source is used to generate near-infrared fundamental frequency laser light. The first laser control component is used to control and split the near-infrared fundamental frequency laser light to form a first fundamental frequency laser light and a second fundamental frequency laser light. The first coupling component and the second coupling component are used to couple the first fundamental frequency laser light and the second fundamental frequency laser light into the near-infrared medical optical fiber and the multifunctional flexible optical cable, respectively. The multifunctional flexible optical cable connects the fundamental frequency laser module and the integrated frequency conversion handle, and includes a near-infrared energy transmission quartz optical fiber, a water inlet pipe, and a water return pipe, which are coated in an outer sheath and spaced apart. The near-infrared energy transmission quartz optical fiber is used to receive the second fundamental frequency laser coupled by the second coupling component and transmit the second fundamental frequency laser to the integrated frequency conversion handle. The water inlet pipe and the water return pipe are connected to the water cooling circulator for conveying cooling water to cool the integrated frequency conversion handle. The integrated frequency conversion handle includes an integrated housing, an output window, and a collimating lens, an input cavity mirror, a mid-infrared frequency conversion crystal, an output cavity mirror, and a second laser control component, which are arranged in the integrated housing and placed in sequence along the transmission optical path. The two ends of the integrated housing are respectively fixed to the multifunctional flexible optical cable and the output window. The second fundamental frequency laser emitted from the multifunctional flexible optical cable is collimated by the collimating lens and then vertically enters an optical parametric oscillator composed of the input cavity mirror, the mid-infrared nonlinear crystal, and the output cavity mirror. After passing through the optical parametric oscillator, the second fundamental frequency laser is converted into signal light, idler light, and residual fundamental frequency laser light. The output cavity mirror selectively outputs signal light in the 2.7μm-3.3μm band and idler light in the 2.7μm-3.3μm band or the 5.7μm-7.3μm band as target mid-infrared medical laser light. The target mid-infrared medical laser light is focused, shaped, and attenuated by the second laser control component before being output from the output window.

2. The handle frequency conversion multifunctional mid-infrared laser medical instrument according to claim 1, characterized in that: The integrated frequency conversion handle further includes a water channel, a crystal heat sink, a beam combiner, an indicator light source and a fundamental frequency light extinction device arranged in the integrated housing; The water channel is connected to the water inlet pipe and the water return pipe; The crystal heat sink is placed around the mid-infrared frequency conversion crystal and connected to the water channel for dissipating heat from the mid-infrared frequency conversion crystal; The indicator light source is used to generate visible indicator light; The beam combiner is placed on the light-emitting side of the output cavity mirror, and is used to separate the remaining fundamental frequency laser light from the target mid-infrared medical laser light and combine the indicator light and the target mid-infrared medical laser light into one beam; The fundamental frequency light extinguisher is connected to the water channel and is used to receive the remaining fundamental frequency laser.

3. The handle frequency conversion multifunctional mid-infrared laser medical instrument according to claim 1, characterized in that: The second laser control component includes a first lens and a second lens arranged on the output light path of the optical parametric oscillator and a translation slide fixed on an integrated housing; One of the first lens and the second lens is fixed in the integrated housing, and the other is fixed on the translation slide. By controlling the movement of the translation slide, the distance between the first lens and the second lens can be adjusted, thereby adjusting the position and size of the target mid-infrared medical laser focal spot.

4. The handle frequency conversion multifunctional mid-infrared laser medical instrument according to claim 1, characterized in that: The multifunctional flexible optical cable also includes a first connector and a second connector placed at both ends, as well as a reinforcing core and a cable control line that are coated in an outer sheath and spaced apart from the near-infrared energy transmission quartz optical fiber, the water inlet pipe, and the water return pipe. The inner sides of the first connector and the second connector are connected to the outer sheath and the reinforcing core, and the outer sides are respectively fixed to the output end of the fundamental frequency laser module and the input end of the integrated frequency conversion handle, and are used to peel off and fix the near-infrared energy transmission quartz optical fiber, the water inlet pipe, the water return pipe, and the cable control line one by one.

5. The handheld frequency conversion multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: The input cavity mirror is coated with a dielectric film that is highly transparent to the second fundamental frequency laser and highly reflective to signal light and idler light; the output cavity mirror is coated with a dielectric film that is highly transparent to the second fundamental frequency laser, has a reflectivity of greater than 40% for signal light, and has a transmittance of greater than 40% for idler light in the 2.7μm~3.3μm band or the 5.7μm~7.3μm band.

6. The handheld frequency-converting multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: The output cavity mirror includes a movable first region, a second region and a third region; The first region has high reflectivity for signal light in the 2.7μm to 3.3μm band and a transmittance of greater than 40% for idler light in the 5.7μm to 7.3μm band; The second region has a transmittance of greater than 40% for signal light in the 2.7μm to 3.2μm band and high reflection for idler light in the 5.7μm to 7.3μm band; The third region has a transmittance greater than 40% for signal light in the 2.7 μm to 3.3 μm band, and a transmittance greater than 40% for idler light in the 2.7 μm to 3.3 μm band and the 5.7 μm to 7.3 μm band.

7. The handheld frequency-converting multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: The wavelength range of the near-infrared fundamental frequency laser is 0.8 μm to 2.5 μm, the single pulse energy is greater than 0.1 mJ, the pulse repetition frequency is 1 Hz to 200 kHz, and the pulse width is 0.1 to 1000 ns.

8. The handheld frequency conversion multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: The first laser control component includes a polarization beam splitter, a rotating stage, and a half-wave plate arranged on the rotating stage. The near-infrared fundamental frequency laser is incident on the polarization beam splitter after being polarization-controlled by the half-wave plate to form the first fundamental frequency laser and the second fundamental frequency laser. The rotating stage is used to adjust the angle of the half-wave plate to control the energy ratio of the first fundamental frequency laser and the second fundamental frequency laser.

9. The handheld frequency-converting multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: It also includes an end light guide pin, which is connected to one end of the integrated frequency conversion handle close to the output window, and is internally provided with a reflection adjustment lens of the target mid-infrared medical laser for adjusting the light output direction of the target mid-infrared medical laser.

10. The handheld frequency-converting multifunctional mid-infrared laser medical instrument according to any one of claims 1 to 4, characterized in that: It also includes a laser power supply, a display control panel and an integrated cabinet. The fundamental frequency laser module, laser power supply and water-cooling circulator are integrated into the integrated cabinet. The control panel is installed on the outside of the shell of the integrated cabinet. The water-cooling circulator is also used to perform water cooling on the fundamental frequency laser module and the integrated frequency conversion handle. The display control panel is electrically connected to the fundamental frequency laser module, laser power supply and water-cooling circulator to provide selection of medical laser parameters such as output power, repetition frequency and cooling water temperature.

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