Techniques for performing safety tests on laser diode ophthalmic surgical devices

Abstract

Aspects of the present disclosure provide techniques for performing a safety test on a laser diode associated with an ophthalmic surgical device. An example method includes determining a measured slope efficiency of a laser diode based on a plurality of different current levels applied to an input of the laser diode and a plurality of different output power levels associated with the laser diode; determining an expected slope efficiency of the laser diode based on the measured operating temperature of the ophthalmic surgical device; determining a result of a safety test of the laser diode based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode; and outputting an electrical signal indicative of a result of the safety test of the laser diode.

Description

Background Art

[0001] In a variety of medical procedures, lasers (e.g., laser treatment beams ("treatment beams"), laser aiming beams ("aiming beams"), etc.) are used to assist surgery and / or treat patient anatomical structures. For example, in laser photocoagulation, a laser probe transmits a laser treatment beam to ablate blood vessels at ablation points on the retina. The laser treatment beam is typically transmitted from a surgical laser system via an optical fiber that terminates proximally in a port adapter that is connected to the surgical laser system and distally in a laser probe that is manipulated by a surgeon. It should be noted that, in this document, the distal end of a component refers to the end that is closer to the patient's body, while the proximal end of a component refers to the end that is away from the patient's body or closer to, for example, a surgical laser system.

[0002] In addition to burning the blood vessels at the burn point, the treatment beam may also damage some rods and cones in the retina that provide vision, thereby affecting vision. Since vision is sharpest at the central macula of the retina, the surgeon arranges the laser probe to produce burn points in the peripheral area of ​​the retina. During the procedure, the surgeon drives the probe with a non-burning aiming beam to illuminate the retinal area to be photocoagulated. Due to the availability of low-power red laser diodes, the aiming beam is usually a low-power red laser. Once the surgeon has positioned the laser probe so as to illuminate the desired retinal point with the aiming beam, the surgeon starts the laser treatment beam through a foot pedal or other device to photocoagulate the illuminated area (e.g., or an area surrounding the illuminated area) using the laser treatment beam. After burning the retinal point, the surgeon repositions the probe to illuminate a new point with the aiming light, starts the laser treatment beam to photocoagulate the new point, repositions the probe, and so on until the desired number of burn laser points are distributed on the retina. Summary of the invention

[0003] Certain embodiments relate to a method for performing a safety test on a laser diode associated with an ophthalmic surgical device. The method may include: measuring an operating temperature of the ophthalmic surgical device; outputting a plurality of different current levels and applying the plurality of different current levels to an input of the laser diode; and determining a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to the input of the laser diode, wherein the plurality of different output power levels include a different output power for each of the plurality of different current levels. The method may also include: determining a measured slope efficiency of the laser diode based on the plurality of different current levels and the plurality of different output power levels; determining an expected slope efficiency of the laser diode based on the measured operating temperature of the ophthalmic surgical device; determining a result of the safety test of the laser diode based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode; and outputting an electrical signal indicative of the result of the safety test of the laser diode.

[0004] In certain embodiments, a device for performing safety testing on a laser diode of an ophthalmic surgical device is provided. The device includes a temperature sensor configured to measure an operating temperature of the ophthalmic surgical device. The device also includes a power module configured to: output a plurality of different current levels; apply the plurality of different current levels to an input terminal of the laser diode; and determine a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to the input terminal of the laser diode, wherein the plurality of different output power levels include a different output power for each different current level of the plurality of different current levels. The device also includes one or more processors configured to: obtain a measured temperature of the ophthalmic surgical device from the temperature sensor; obtain an indication of the multiple different output power levels and the multiple different current levels from the power module; determine a measured slope efficiency of the laser diode based on the multiple different current levels and the multiple different output power levels; determine an expected slope efficiency of the laser diode based on the measured operating temperature of the ophthalmic surgical device; determine a result of a safety test of the laser diode based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode; and output an electrical signal indicative of the result of the safety test of the laser diode. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] In order to be able to understand the above-mentioned features of the present disclosure in detail, the present disclosure briefly summarized above can be described in more detail with reference to the embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only show exemplary embodiments and are therefore not to be considered as limiting the scope thereof, and other equally effective embodiments may be allowed.

[0006] Figure 1 A plan view of a system for generating a laser beam for delivery to a surgical target is shown in accordance with certain embodiments of the present disclosure.

[0007] Figure 2 Examples of surgical laser systems and components therein according to certain embodiments of the present disclosure are shown.

[0008] Figure 3 A graph including multiple curves depicting optical output power versus forward current of a red laser diode at different temperatures is shown.

[0009] Figure 4 An example procedure for performing safety testing on laser diodes for ophthalmic surgical equipment is presented.

[0010] Figure 5 Included is a graph showing slope efficiency versus temperature for a red laser diode according to certain embodiments.

[0011] Figure 6 Included is a graph showing slope efficiency versus temperature for a red laser diode according to certain embodiments.

[0012] Figure 7 Included is a graph illustrating the effect of aging on the slope efficiency versus temperature of a red laser diode in accordance with certain embodiments.

[0013] Figure 8 The region within which the slope efficiency of a red laser diode according to certain embodiments is expected to fall is shown.

[0014] Fig. 9 Results of safety testing to determine a red laser diode according to some embodiments are presented in graphical form.

[0015] Fig.10 An exemplary diagram is presented that illustrates how various components of an ophthalmic surgical device used in conjunction with certain embodiments described herein communicate and operate together.

[0016] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0017] In the following description, details are set forth by way of example to facilitate understanding of the disclosed subject matter. However, it is clear to those of ordinary skill in the art that the disclosed embodiments are exemplary and are not exhaustive of all possible embodiments. Therefore, it should be understood that the reference to the described examples is not intended to limit the scope of the present disclosure. Those skilled in the art in the technical field involved in the present disclosure are generally fully able to envision any changes and further modifications to the described devices, instruments, methods, and any further applications of the principles of the present disclosure. In particular, it is fully envisioned that the features, components, and / or steps described for one embodiment can be combined with the features, components, and / or steps described for other embodiments of the present disclosure.

[0018] It should be noted that as described herein, the distal end, distal segment, or distal portion of a component refers to the end, segment, or portion that is closer to the patient's body during use of the component. On the other hand, the proximal end, proximal segment, or proximal portion of a component refers to the end, segment, or portion that is farther from the patient's body, closer to, for example, a surgical laser system.

[0019] As used herein, the term "about" or approximately can refer to a + / - 10% variation from the nominal value. It should be understood that such variations can be included in any value provided herein.

[0020] Example Surgical Laser System

[0021] Figure 1 An example system 100 for performing laser-assisted ophthalmic procedures according to certain embodiments is shown. System 100 includes a surgical laser system 102 having one or more laser sources for generating laser beams. For example, a first laser source within surgical laser system 102 can generate a treatment beam having a first wavelength (e.g., approximately 532 nanometers (nm)), while a second laser source can generate an aiming beam having a second wavelength (e.g., approximately 635 nm). A user (e.g., a surgeon) can first trigger surgical laser system 102 (e.g., via a foot switch, voice command, etc.) to emit an aiming beam onto a desired retinal point. Once the surgeon has positioned the laser probe so as to illuminate the desired retinal point with the aiming beam, the surgeon activates the treatment beam, such as via a foot pedal or other device, to treat the patient's anatomy (e.g., photocoagulate the desired retinal point using the treatment beam).

[0022] As shown, the surgical laser system 102 includes a connector or port adapter 114 that couples to an optical port of the surgical laser system 102 . Figure 1Also shown is an optical fiber 110 within a fiber optic cable 111 having a distal end coupled to and extending through the probe 108 and a proximal end coupled to and extending through a port adapter 114. In some cases, as further described herein, the optical fiber 110 may include more than one optical fiber. Figure 1 In the example of , the port adapter 114 includes a ferrule having an opening into which the proximal end of the optical fiber 110 is inserted. The proximal end of the optical fiber 110 includes an interface plane (also referred to as a proximal entrance plane) onto which a laser beam from the surgical laser system 102 can be focused when the proximal end of the optical fiber 110 is inserted into the ferrule. The interface plane of the optical fiber 110 includes exposed proximal ends of one or more cores to which the laser beam can be directed. Figure 1 In the example of FIG. 1 , optical fiber 110 is a multi-core optical fiber (MCF) having four cores. Thus, the interface plane at the proximal end of optical fiber 110 includes the proximal ends of the four cores, and the laser beam can be focused on the proximal ends of the four cores. In some cases, optical fiber 110 can be a single-core optical fiber having only one core.

[0023] The surgical laser system 102 can be configured to split a single laser beam generated by a laser source into a plurality of laser beams exhibiting a laser dot pattern. For example, the surgical laser system 102 can split an aiming beam into four aiming beams, and then deliver the four aiming beams to the interface plane of the optical fiber 110 through the opening of the ferrule of the port adapter 114. The surgical laser system 102 can be further configured to split a therapeutic beam into four therapeutic beams, and deliver the four therapeutic beams to the interface plane of the optical fiber 110 through the opening of the ferrule. In such an example, each core of the optical fiber 110 can transmit a multi-wavelength or combined beam, which can refer to a therapeutic beam combined with an aiming beam. Although certain aspects are described with respect to the core of the optical fiber transmitting a combined beam, it should be noted that the core of the optical fiber 110 can also transmit a therapeutic beam or an aiming beam alone, depending on which beam is activated and incident on the optical fiber 110.

[0024] In some examples, the surgical laser system 102 can also propagate an illumination beam into the interface plane of the optical fiber 110 (e.g., the interface plane of the optical fiber can also include the proximal end of the cladding that holds the core within the optical fiber 110) to illuminate the interior of the eye, particularly the area to be photocoagulated of the retina 120. In some aspects, the illumination beam can be generated by a white light emitting diode (LED).

[0025] The optical fiber 110 delivers the combined light beam to the probe 108, which propagates a multi-point pattern (e.g., four points) of the combined light beam to the retina 120 of the patient's eye 125. The probe 108 includes a probe body 112 and a probe tip 140 that houses and protects the distal end of the optical fiber 110. The distal portion 145 of the probe tip 140 can also house a lens that focuses the combined light beam on the retina 120.

[0026] Figure 2 An example surgical laser system 202 and components therein that may be implemented according to embodiments described herein are shown. The surgical laser system 202 is an example embodiment of the surgical laser system 102. The surgical laser system 202 includes a laser source 204 that propagates a treatment beam 210, a laser source 206 that propagates an aiming beam 212, and a light source 208 that propagates an illumination beam 214. The surgical laser system 202 further includes a plurality of lenses, diffractive elements, beam splitters, and other optical relay devices for relaying the laser beams and the illumination beams between their respective sources and the desired ports, which may be collectively referred to as an "optical relay system."

[0027] At the beginning of the operation, the surgeon can start the light source 208 to illuminate the inside of the eyeball and make it easier to view the retina. As shown, once emitted by the light source 208, the illumination beam 214 (stippling section) is received by the collimating lens 222, which is configured to produce a beam with parallel light rays. In some embodiments, the collimating lens 222 can be a multi-element achromatic lens including two singlet lenses and a doublet lens. Therefore, as shown, the illumination beam 214 is emitted together with the parallel light rays from the other side of the collimating lens 222, and passes through beam splitters 228 and 226 (they can also be referred to as dichroic mirrors) respectively, and arrives at the converging lens 224. In some embodiments, the converging lens 224 can be a multi-element achromatic lens including two singlet lenses and a doublet lens. In such an embodiment, except that the assembly is inverted (e.g., rotated 180 degrees), the converging lens 224 can have the same design as the collimating lens 222, thereby creating a one-to-one magnification imaging system. Each of the beam splitters 228 and 226 can have different coatings on its two sides 228a and 228b and 226a and 226b, respectively. For example, the sides 228a and 226a are coated so that they allow light propagating thereon to pass through the beam splitters 228 and 226. Thus, a majority of the illumination beam 214 propagating to the sides 228a and 226a passes through the beam splitters 228 and 226. On the other hand, the sides 228b and 226b are coated to reflect light or laser beams (such as the aiming beam 212 and the treatment beam 210), respectively, as further described below.

[0028] Converging lens 224 then focuses illumination beam 214 into an interface plane at the proximal end of an optical fiber, such as optical fiber 110, which is coupled to port 225 of surgical laser system 202 via port adapter 114. Figure 1 As described, the optical fiber 110 may have four cores in a 2×2 array embedded in a larger diameter cylindrical cladding. Thus, the converging lens 224 focuses the illumination beam 214 into the interface plane of the optical fiber 110 so that the illumination beam 214 propagates along the entire length of the cladding and each of the four cores of the optical fiber 110 and through its entire diameter to a surgical probe (e.g., Figure 1 As described above, the interface plane of the optical fiber 110 includes the proximal ends of the four cores and their claddings, which are exposed through the openings 217 of the port adapter 114 via the ferrules 215, respectively.

[0029] Once the surgeon is able to view the inside of the eyeball, the surgeon can project one or more desired aiming beam points onto the retina from the distal end of the probe. More specifically, upon activation by the surgeon, the laser source 206 emits an aiming beam 212 (e.g., a red laser beam) onto a diffractive optical element (DOE) 221. The diffractive segments may also be referred to herein as "segments". Figure 2 In the example of , DOE 221 is positioned so that aiming beam 212 is aligned with the middle section of DOE 221, which diffracts aiming beam 212 into aiming beams 212a-d (e.g., four aiming beams). However, the surgeon can change the position of DOE 221 so as to diffract the beam into a different number of beams (e.g., 2 or 1). For example, using voice commands or some other feature of surgical laser system 202, the surgeon can position DOE 221 so that aiming beam 212 is aligned with a different section of DOE 221, which can diffract aiming beam 212 into two or one or another number of beams.

[0030] Once diffracted, the resulting aiming beams are reflected by beam splitter 228 through beam splitter 226 and onto converging lens 224. In the example where aiming beams 212a-d are red aiming beams, beam splitter 228 may be a red dichroic optical element, and aiming beams 212a-d may be reflected by the narrow-band red spectral notch in beam splitter 228. Converging lens 224 then focuses the four aiming beams onto the interface plane at the proximal end of optical fiber 110 such that each aiming beam propagates along the entire length of the corresponding core of optical fiber 110 to a surgical probe (e.g., Figure 1Each of the four aiming beams is focused into a corresponding core within the 4-core MCF with high coupling efficiency and propagates along the length of the core to the distal end of the MCF. This allows the surgeon to project four desired aiming beam points onto the retina from the distal end of the probe.

[0031] As described above, once the surgeon has positioned and activated the laser probe so as to project the aiming beam spot onto the retina, the surgeon activates the laser source 204, such as by a foot pedal or other device, to treat the patient's anatomy (e.g., photocoagulate the desired retinal spot using a treatment beam). When activated, the laser source 204 emits a treatment beam 210, such as a green laser beam, such as Figure 2 As shown. The treatment beam 210 reaches the beam splitter 213, which is configured to allow most of the treatment beam 210 to pass through, while reflecting an insignificant portion 231 onto the sensor 223. The sensor 223 is an optical sensor configured to detect whether the laser source 204 is active and monitor the power of the treatment beam. After passing through the beam splitter 213 and as long as the shutter 234 is in the open position to allow the treatment beam 210 to enter, the treatment beam 210 is received at the fixed folding reflector 219, which is configured to reflect the treatment beam 210 onto the beam splitter 218.

[0032] As described above, the surgical laser system 202 may also include a shutter 234 disposed between the laser source 204 and the fixed folding mirror 219. The shutter 234 may be configured to alternately block or allow the treatment beam 210 to reach the fixed folding mirror 219. The surgeon or surgical staff may control the shutter 234 (e.g., via a foot switch, voice command, etc.) to emit a laser aiming beam and emit a treatment laser beam (e.g., open the shutter 234) to treat the patient's anatomy (e.g., perform photocoagulation). In each case, the beam splitter 218 may direct the laser beam toward the port adapter 114.

[0033] As shown, the treatment beam 210 passes through a beam splitter 218 before reaching the DOE 220. Similar to the DOE 221, the DOE 220 then diffracts the treatment beam 210 into treatment beams 210a-210d (e.g., four treatment beams). However, the surgeon can change the position of the DOE 220 so as to diffract the beam into a different number of beams (e.g., 2 or 1). For example, using voice commands or some other feature of the surgical laser system 202, the surgeon can position the DOE 220 to align the treatment beam 210 with different sections of the DOE 220, which can diffract the treatment beam 210 into two or one or other number of beams. In some cases, a 2×2 array of four red laser aiming beams 212a-d and a 2×2 array of four green laser treatment beams 210a-210d can be coupled into the four cores and confined within the four cores without spilling into the surrounding cylindrical cladding.

[0034] The treatment beams 210a-210d are then received at the beam splitter 226, which reflects the treatment beams 210a-210d onto the converging lens 224. In an example where the treatment beams 210a-d are green treatment beams, the beam splitter 226 can be a green dichroic optical element, and the treatment beams 210a-d can be reflected by a narrow-band green spectral notch in the beam splitter 226. The treatment beams 210a-d are reflected by the beam splitter 226 at an angle relative to the beam splitter 226 that is equal to the angle at which the aiming beams 212a-d pass through the beam splitter 226. Thus, when the laser source 204 is active, the transmitted treatment beams 210a-d and the aiming beams 212a-d are combined (e.g., such that they overlap one another), thereby creating combined beams 211a-d, which then reach the converging lens 224.

[0035] The converging lens 224 focuses the combined light beams 211a-211d onto the interface plane at the proximal end of the optical fiber 110 so that each of the combined light beams 211a-211d propagates along the entire length of the corresponding core of the optical fiber 110 to the surgical probe (e.g., Figure 1 More specifically, at the distal end of the probe 108. Figure 2 In the example of FIG. 1 , the optical fiber 110 is an MCF having four cores (e.g., core A, core B, core C, and core D). In this example, the converging lens 224 focuses the combined beams 211a-211d onto the interface plane at the proximal end of the optical fiber 110, so that, for example, the combined beam 211a propagates to core A, the combined beam 211b propagates to core B, the combined beam 211c propagates to core C, and the combined beam 211d propagates to core D. Although Figure 2An embodiment is shown for splitting the treatment beam 210 into four treatment beams 210a-d and focusing each of the treatment beams 210a-d onto a separate core, but it should be understood that only one treatment beam may be used and focused onto a single core optical fiber. Figure 2 An embodiment is shown for splitting aiming beam 212 into four aiming beams 212a-d and focusing each of aiming beams 212a-d onto a separate core, but it is understood that only one aiming beam may be used and focused onto a single core optical fiber.

[0036] In addition, as shown in the figure, Figure 2 The surgical laser system 202 includes: a temperature sensor 244, which is configured to monitor / sense the temperature of the surgical laser system 202; one or more processors 252, which are configured to retrieve and execute programming instructions stored in a memory 254 for operating one or more components of the surgical laser system 202; and a power module 242, which is configured to power one or more components of the surgical laser system 202 (e.g., laser source 204, laser source 206, etc.). In addition, Figure 2 A display 256 is included, which is configured to display the Figure 2 The information output by the surgical laser system 202. Additional aspects regarding the temperature sensor 244, the one or more processors 252, the memory 254, the power module 242, and the display 256 are described below.

[0037] Aspects of safety testing of laser diodes in ophthalmic surgical equipment

[0038] As mentioned above, Figure 2 The surgical laser system 202 includes a laser source 206 that transmits an aiming beam 212. In some cases, the laser source 206 may include a red laser diode 240, which may be subject to laser classification restrictions for eye safety purposes. For example, the red laser diode 240 may be subject to Class 2 laser restrictions, thereby limiting the output of the red laser diode 240 to one milliwatt (mW) of continuous wave output power accessible to the human eye. In some cases, to help ensure that the emission power of the red laser diode 240 does not exceed the maximum power level of the Class 2 laser (e.g., 1 mW), the surgical laser system 202 includes a power module 242. For example, the power module 242 can be configured to measure the radiated output power of the red laser diode 240 based on a portion of the aiming beam 212, and adjust the power supplied to the red laser diode 240 based on the measured output power so that the red laser diode 240 does not exceed the maximum power level of the Class 2 laser.

[0039] While the above-described methods can help avoid situations where the radiated output power of the red laser diode 240 exceeds the maximum power level, these methods rely on the power module 242 never failing. However, if the power module 242 fails, and if it fails in such a way that the emitted power of the red laser diode 240 appears to be much less than the actual emitted power of the red laser diode 240, this situation can create a dangerous looping situation in which the power module 242 responds by increasing the current / power supplied to the red laser diode 240 to compensate for the seemingly low power, thereby causing the output power of the red laser diode 240 to be much higher than the maximum power level allowed.

[0040] In some cases, to protect against situations where the power module 242 fails and the output power of the red laser diode 240 exceeds a maximum power level, a backup system can be created that relies on (1) capping the current of the red laser diode 240 and (2) tightly controlling the temperature of the red laser diode 240. However, one problem with this type of system is that (a) controlling current is a poor way to control output power without tightly controlling temperature, as explained above, and (b) tightly controlling diode temperature is complex and expensive.

[0041] For example, Figure 3 A graph 300 including a plurality of curves 302-308 is shown, which depict optical output power versus forward current of a red laser diode 240 at different temperatures, such as 0°C, 25°C, 40°C, and 50°C. The output power versus forward current of the red laser diode has a characteristic hockey stick shape, divided into three different regions: (1) a light emitting diode (LED) region 314 in a low current region, where the red laser diode 240 is not yet lasing but is emitting incoherent LED light, and where the linear increase in output power versus forward current is low; (2) a lasing region 316 in a high current region, where the diode is lasing, and where the linear increase in output power versus forward current is high; and (3) a transition region 318 between the LED region 314 and the lasing region 316, which is typically narrow and within a small forward current range. As shown in FIG. Figure 3 As shown, the slope of LED region 314 appears to be zero, and transition region 318 appears to have a zero current width. However, the slope of LED region 314 is non-zero, but very small. Similarly, the current width of transition region 318 is also non-zero, but very small.

[0042] like Figure 3As shown in curve 306 in FIG. 3 , for a temperature of 40° C., supplying a forward current of approximately 35 milliamperes (mA) to the red laser diode 240 causes the output power of the red laser diode 240 to be at a maximum power level of 1 mW as shown at 310. However, when the temperature is below 40° C., supplying this same amount of forward current (e.g., 35 mA) will cause the output power of the red laser diode 240 to exceed the maximum power level of 1 mW. For example, as shown in curve 304, at a temperature of 25° C., supplying 35 mA to the red laser diode 240 produces (as shown at 312) an output power of the red laser diode 240 of approximately 6 mW, resulting in the red laser diode 240 no longer being classified as a Class 2 laser and potentially causing eye damage.

[0043] Accordingly, as in Figure 3 , small fluctuations in operating temperature may cause significant fluctuations in the output power of the red laser diode 240. In some cases, such as when the surgical laser system 202 is powered on and begins to heat up due to heat dissipation of the various components of the surgical laser system 202, these temperature fluctuations may occur. In addition, part-to-part laser diode variability may cause each red laser diode to have a different, unique output power versus forward current relationship, such that currents and temperatures that maintain the output power below the maximum power level of one red laser diode may allow the output power to significantly exceed the maximum power level of a different red laser diode.

[0044] Accordingly, aspects of the present disclosure provide techniques for reducing the probability of an ophthalmic surgical device's laser diode (such as the red laser diode 240 in the surgical laser system 202) accidentally operating above the maximum power level of the laser diode. In some cases, these techniques may involve performing a safety test on the ophthalmic surgical device's laser diode to determine whether the laser diode is safe to use. In some cases, to avoid temperature variability associated with the forward current and output power of the laser diode described above, the safety test may take into account the slope efficiency of the laser diode (e.g., the change in the output power of the laser diode divided by the change in the forward current of the laser diode), which may not be easily changed due to temperature changes.

[0045] Example operations for performing safety tests associated with a laser diode

[0046] Figure 4 An example process 400 for performing safety testing on a laser diode of an ophthalmic surgical device, such as the red laser diode 240 of the surgical laser system 202 , is presented.

[0047] Process 400 begins by measuring the operating temperature of surgical laser system 202 at 410. In some cases, surgical laser system 202 may use a temperature sensor (e.g., Figure 2 The temperature of the surgical laser system 202 is shown using a temperature sensor 244 to measure the temperature.

[0048] At 420, surgical laser system 202 outputs a plurality of different current levels (e.g., 10 mA, 12 mA, 14 mA, 16 mA, and 18 mA) and applies the plurality of different current levels to the input of red laser diode 240. For example, in some cases, power module 242 may include a digital-to-analog converter (DAC) configured to output a plurality of different current levels in response to different voltage levels applied to the DAC and apply the plurality of different current levels to the input of red laser diode 240. In some cases, power module 242 may include an internal ammeter that may be configured to measure the plurality of different current levels applied to the input of red laser diode 240.

[0049] At 430, surgical laser system 202 determines a plurality of output power levels associated with red laser diode 240 based on a plurality of different current levels applied to the input of red laser diode 240. In some cases, the plurality of output power levels includes a different output power for each of the plurality of different current levels. In some cases, to determine the plurality of different output power levels associated with the laser diode, power module 242 of surgical laser system 202 may be configured to measure a plurality of output voltage levels associated with red laser diode 240. In such a case, each of the plurality of output voltage levels may correspond to a different current level of the plurality of different current levels applied by power module 242 to the input of red laser diode 240.

[0050] The power module 242 may then convert the plurality of output voltage levels into a plurality of different output power levels based on a plurality of different current levels applied to the input of the red laser diode 240 and correlation data indicating a correlation between the output voltage level and the output power level of the red laser diode 240 stored in the memory 254 of the surgical laser system 202. For example, during calibration of the surgical laser system 202, the output voltage level of the red laser diode 240 may be correlated to the output power level of the red laser diode 240 by comparing the measured voltage of the red laser diode 240 to the output power of the red laser diode 240 for two or more different input current levels. Thereafter, interpolation may be performed using the measured voltage and output power for the two or more different input current levels to generate a conversion or correlation between the voltage level and the output power level of the red laser diode 240. Accordingly, during safety testing, the power module 242 may convert the plurality of output voltage levels into a plurality of different output power levels for a plurality of different current levels applied to the input of the red laser diode 240 using the correlation data stored in the memory 254.

[0051] The power module 242 may know the current level (I) applied to the input of the red laser diode 240 and the measured output voltage level (V) corresponding to this applied current level. Thus, the power module 242 may use the equation P=I*V to determine the output power level of the red laser diode 240 for a given current level applied to the input of the red laser diode 240.

[0052] Afterwards, in Figure 4 At 440, the surgical laser system 202 determines a measured slope efficiency of the red laser diode 240 based on the plurality of different current levels and the plurality of different output power levels. In some cases, the measured slope efficiency of the red laser diode 240 may be determined by one or more processors 252 of the surgical laser system 202. For example, the one or more processors 252 may obtain an indication of the plurality of different output power levels and the plurality of different current levels from the power module 242. The one or more processors may then determine the measured slope efficiency of the red laser diode 240 based on the plurality of different current levels and the plurality of different output power levels.

[0053] As described above, the slope efficiency of the red laser diode 240 (e.g., the change in output power of the red laser diode 240 divided by the change in forward current of the red laser diode 240) may not be easily changed due to temperature changes compared to the relationship between the forward current and output power of the red laser diode 240. For example, Figure 5 The graph includes a graph showing the slope efficiency (eg, mW / mA) of the red laser diode 240 versus temperature (TC ) is a graph 500 showing the relationship between the slope efficiency (S 1 Due to the relative stability of the slope efficiency to the varying operating temperatures associated with the red laser diode 240 (e.g., compared to the forward current versus output power of the red laser diode 240), performing safety testing on the red laser diode 240 based on the slope efficiency is more reliable.

[0054] As described above, the slope efficiency of the red laser diode 240 represents the change in the output power of the red laser diode 240 divided by the change in the forward current of the red laser diode 240. Accordingly, in some cases, to determine the measured slope efficiency of the laser diode, the one or more processors 252 can be configured to determine a first difference between a plurality of different output power levels and to determine a second difference between a plurality of different current levels. Thereafter, the one or more processors 252 can determine a ratio of the first difference to the second difference. The measured slope efficiency determined by the one or more processors 252 includes the determined ratio between the first difference and the second difference.

[0055] As an example, assume that the power module 242 is configured to provide two current levels (eg, I 1 and I 2 ) is applied to the input of the red laser diode 240 and determines two output power levels (eg, P 1 and P 2 In this example, the one or more processors 252 may calculate the slope efficiency (S ) of the red laser diode 240 at the operating temperature and time (t). 1 ) is determined as

[0056] Thereafter, at 450 , surgical laser system 202 determines an expected slope efficiency of red laser diode 240 based on the measured operating temperature (T) and one or more calibration parameters associated with when red laser diode 240 was initially calibrated.

[0057] For example, the one or more processors 252 may be configured to further determine the red laser diode 240 based on a calibration temperature (T cal ), the calibration slope efficiency (S ) associated with when the red laser diode 240 is initially calibrated cal ), and one or more aging correction factors to determine the expected slope efficiency of the red laser diode 240.

[0058] For example, during calibration of surgical laser system 202, the calibration temperature (Tcal ) and calibration slope efficiency (S cal ) can be recorded and stored in the memory 254 of the surgical laser system 202. In some cases, the LED zone associated with the red laser diode 240 (such as Figure 3 The LED area 314 is shown to measure the calibration temperature (T cal ) and calibration slope efficiency (S cal ). In some cases, the following equation 1 shows the relationship based on S cal and T cal The relationship between slope efficiency and temperature of the red laser diode 240 at time zero (eg, when the surgical laser system 202 is calibrated).

[0059] S(0,T)=S o T=S cal +S′ o (TT cal ) (1)

[0060] As shown, Equation 1 includes a slope called the "slope efficiency" (S' o ) is another parameter that is a measure of the rate at which the slope efficiency changes with the temperature of the red laser diode 240. The slope of the slope efficiency (S′) o ) may include an average slope (S′) of a slope term established based on experimental data associated with the surgical laser system 202 o-ave ) (e.g., approximately −0.0287 μW / mA / ° C.) and the slope of the slope uncertainty standard deviation term also established based on experimental data associated with the surgical laser system 202 (For example, approximately 0.002481 μW / mA / °C). Figure 6 The effect of the slope of the slope efficiency on the relationship between the slope efficiency and temperature is shown in FIG.

[0061] For example, Figure 6 A graph 600 is included showing the slope efficiency versus temperature of the red laser diode 240 based on Equation 1. As shown, Figure 6 The calibration temperature (T cal ) and calibration slope efficiency (S cal ) data point 602. Based on T cal and S cal , by targeting the minimum operating temperature (T min ) and the maximum operating temperature (T max ) using Equation 1, the expected slope efficiency of the red laser diode 240 can be extrapolated. Figure 6In FIG. 6 , curve 606 represents the average expected slope efficiency of the red laser diode 240 at a given temperature. Further, the average expected slope efficiency of the red laser diode 240 at a given temperature may be due to the slope of the slope efficiency (S′) of Equation 1. o ) parameter uncertainty term, thereby generating a region 604 representing a range of possible expected slope efficiency values ​​at different temperatures. Figure 6 As shown, at a given T cal and S cal In the case of minimum operating temperature (T min ), the expected slope efficiency of the red laser diode 240 can be within the range between the slope efficiency X and the slope efficiency Y based on Equation 1.

[0062] In some cases, the relationship between the slope efficiency and temperature of the red laser diode 240 may change over time as the red laser diode ages. Figure 7 As shown, the red laser diode 240 is at T cal The slope efficiency (S) under the condition tends to increase over time (but may also decrease slightly), as shown at 702, while the slope of the slope efficiency (S′ o ) tends to become more steeply negative, as shown at 704. To help correct for the effects of aging on the relationship between the slope efficiency and temperature of the red laser diode 240, a number of aging correction factors may be added to Equation 1, as shown below in Equation 2.

[0063] S(t,T)=S cal ·(1+C)+(1+R)·S o '·(TT cal ) (2)

[0064] In some cases, one or more processors 252 of surgical laser system 202 may be configured to: Figure 4 Equation 2 is used at 450 to determine the expected slope efficiency of the red laser diode 240 at time t (e.g., the time since the beginning of the life of the red diode when the safety test is performed on the red laser diode 240) and temperature T (e.g., the operating temperature measured at 410 during the safety test). As shown, Equation 2 includes two aging correction factors: a first aging correction factor (C) and a second aging correction factor (R). The first aging correction factor (C) is applied to the calibrated slope efficiency (e.g., the slope efficiency S measured during calibration). cal ), and correcting for the effects of aging on the slope efficiency of the red laser diode 240 (e.g., Figure 7The second aging correction factor (R) is applied to the slope of the slope efficiency (S o ′), and correcting the slope of the slope efficiency associated with the red laser diode 240 for aging (S o ′) (e.g. Figure 7 In some cases, the first aging correction factor (C), the second aging correction factor (R), and the slope of the slope efficiency (S o ′) may be stored in the memory 254 of the surgical laser system 202 .

[0065] In some cases, in order to consider the first aging correction factor (C), the second aging correction factor (R), and the slope of the slope efficiency (S o ′), the one or more processors 252 of the surgical laser system 202 may be further configured to determine a range of expected slope efficiencies for the red laser diode 240. For example, in some cases, the range of expected slope efficiencies for the laser diode may include a certain number of standard deviations above and below the expected slope efficiency of the red laser diode 240, such as two or three standard deviations, thereby yielding a maximum expected slope efficiency (S max ) and the minimum expected slope efficiency (S min ).

[0066] like Figure 8 As shown, the range of expected slope efficiencies of the red laser diode 240 can be calculated using Equation 2 for different temperatures (e.g., range T min With T max to generate the actual slope efficiency of the red laser diode 240 (e.g., at different temperatures between Figure 4 The measured slope efficiency determined at 440 of ) is expected to fall within region 802. Figure 8 In the figure, the boundary line 804 indicates that the red laser diode 240 is within the range of T min With T max The maximum expected slope efficiency (S max ), and can be determined by adding a certain number of standard deviations to the expected slope efficiency of the red laser diode 240 at a given temperature. Similarly, boundary line 806 represents the slope efficiency of the red laser diode 240 in the range T min With T max The minimum expected slope efficiency (S min ), and can be determined by subtracting a certain number of standard deviations from the expected slope efficiency of the red laser diode 240 at a given temperature.

[0067] Return now Figure 4 At 460, the surgical laser system 202 determines a result of the safety test of the red laser diode 240 based on the measured slope efficiency of the red laser diode 240 determined at 440 and the expected slope efficiency of the red laser diode 240 determined at 450. Thereafter, at 470, the surgical laser system 202 outputs an electrical signal indicating the result of the safety of the laser diode. For example, in some cases, the electrical signal may be output by the one or more processors 252 and displayed on a display 256 associated with the surgical laser system 202.

[0068] In some cases, to determine the results of the safety test of the laser diode, one or more processors 252 of surgical laser system 202 may be further configured to determine whether the measured slope efficiency of red laser diode 240 is consistent with a range of expected slope efficiencies for red laser diode 240 . Fig. 9 The results of the safety test determined based on whether the measured slope efficiency of the red laser diode 240 is consistent with the range of expected slope efficiency of the red laser diode 240 are presented in graphical form.

[0069] For example, Fig. 9 Shows that including the expression for T min With T max FIG. 9 is a graph 900 of a region 802 of different expected slope efficiency ranges for the red laser diode 240 determined according to Equation 2 for different temperatures between 0 and 100 . As described above, the region 802 is bounded by a boundary line 804 representing a maximum expected slope efficiency at a particular temperature. As shown, the boundary line 804 represents three standard deviations (+3σ) above the expected slope efficiency at a particular temperature determined according to Equation 2. Similarly, as described above, the region 802 is bounded by a boundary line 806 representing a minimum expected slope efficiency at a particular temperature. As shown, the boundary line 806 represents three standard deviations (+3σ) below the expected slope efficiency at a particular temperature determined according to Equation 2.

[0070] like Fig. 9 As shown, four different regions are shown in the graph 900, each region being associated with a different safety test result outcome. For example, as shown, the graph 900 includes a first region 902 that is consistent with the region 802, which is associated with a passed safety test. When the measured slope efficiency of the red laser diode 240 (e.g., the measured slope efficiency determined at 440) is consistent within the first region 902, the result of the safety test can be considered to be passed.

[0071] More specifically, for example, as described above, in Figure 4Determining the expected slope efficiency of the red laser diode 240 at 450 includes determining (e.g., for time t and operating temperature T measured at 410) a range of expected slope efficiencies of the red laser diode 240 that includes a certain number of standard deviations above and below the expected slope efficiency of the red laser diode 240, thereby producing a maximum expected slope efficiency (S max ) and the minimum expected slope efficiency (S min Here, the maximum expected slope efficiency (S max ) and the minimum expected slope efficiency (S min ) are points on boundary lines 804 and 806 for time t and temperature T (eg, the operating temperature measured at 410 ), respectively, and define a first zone 902 .

[0072] Accordingly, when the measured slope efficiency of the red laser diode 240 determined at 440 is consistent with the range of expected slope efficiencies of the red laser diode 240 (eg, the measured slope efficiency is consistent with the range defined in S max With S min , the safety test of the red laser diode 240 can be considered to have passed. In this case, the electrical signal output by the one or more processors 252 can indicate on the display 256 that the red laser diode 240 has passed the safety test. In general, the safety test passed can be defined according to the following equation 3.

[0073]

[0074] In Equation 3, S expt It is aimed at Figure 4 The measured operating temperature of the surgical laser system 202 is determined at 410 while Figure 4 The expected slope efficiency of the red laser diode 240 determined at 450, is the third standard deviation of the expected slope efficiency, and S meas is Figure 4 The measured slope efficiency of the red laser diode 240 is determined at 440 of . In other words, is the minimum expected slope efficiency (S) of the surgical laser system 202 at the measured operating temperature. min ), while in Equation 3 is the maximum expected slope efficiency (S) of the surgical laser system 202 at the measured operating temperature max ).

[0075] Furthermore, as shown in the figure, Fig. 9The graph 900 in FIG. 4 includes a second region associated with a failed safety test. When the measured slope efficiency of the red laser diode 240 (e.g., the measured slope efficiency determined at 440) is consistent within the second region 904 defined by the safety boundary line 906, the result of the safety test can be considered to be a failed test.

[0076] As described above, the red laser diode 240 is associated with a specific laser classification (such as laser classification type 2) for performing ophthalmic surgery. In some cases, the safety threshold defining the safety margin line 906 may include a maximum output power (P 2 ) and the maximum output power (P max In other words, the safety threshold can be calculated based on K=P 2 / P max When the red laser diode does not operate normally, such as when S meas Less than S min The estimated maximum power P of each laser spot associated with the red laser diode 240 is max ′ (e.g., depending on whether the optical fiber 110 associated with the red laser diode 240 is single-core or multi-core) can be estimated as P max (S min / S meas ). In some cases, K can be inferred to be S min / S meas The maximum power P allowed for each laser spot max ′ Up to Class 2 power limit P per laser point 2 , but not higher than it. Therefore, P meas The lower power limit can be defined by equation # and rewriting equation #+1.

[0077] P max ·(S min / S meas )≤P 2 (4)

[0078] s meas ≥S min / K (5)

[0079] Because S min decreases with temperature T and K is a fixed constant, so S meas The safety margin line 906 is the minimum allowable S at the edge of the second zone 904. meas Threshold boundary for temperature T.

[0080] Accordingly, when the measured slope efficiency of the red laser diode 240 is inconsistent with the range of the expected slope efficiency of the red laser diode 240 (for example, the measured slope efficiency is not within the range of S max With S min ), and when the measured slope efficiency of the laser diode is less than a safety threshold associated with the laser diode 240 (e.g., the safety boundary line 906 defining the second zone 904), the result of the safety test may be considered a failure. Figure 4 The electrical signal output by the one or more processors 252 at 470 may indicate that the red laser diode 240 has failed the safety test. In some cases, the one or more processors 252 of the surgical laser system 202 may be configured to disable the red laser diode 240 in response to the failed safety test.

[0081] Generally, a failed safety test can be defined according to Equation 6 below.

[0082]

[0083] In Equation 6, S meas is Figure 4 The measured slope efficiency, P, of the red laser diode 240 is determined at 440 max is the maximum output power associated with normal operation of the red laser diode 240, P 2 is the maximum output power associated with the particular laser class of red laser diode 240, S expt It is aimed at Figure 4 The measured operating temperature of the surgical laser system 202 is determined at 410 while Figure 4 The expected slope efficiency of the red laser diode 240 is determined at 450, and is the third standard deviation of the expected slope efficiency.

[0084] Accordingly, when the measured slope efficiency of the red laser diode 240 is inconsistent with the range of the expected slope efficiency of the red laser diode 240 (for example, the measured slope efficiency is not within the range of S max With S min ), and when the measured slope efficiency of the laser diode is greater than or equal to the safety threshold associated with the red laser diode, the electrical signal output by the one or more processors 252 may indicate a warning condition associated with the safety test of the laser diode. For example, when the measured slope efficiency of the red laser diode 240 falls between Fig. 9 This warning condition may be indicated within the third zone 908 or the fourth zone 910 of the illustrated graph 900 .

[0085] If the measured slope efficiency of the red laser diode 240 falls within the third region 908, then the measured slope efficiency of the red laser diode 240 is lower than expected (eg, lower than a minimum expected slope efficiency (S min )). If this situation is caused by a fault in the power monitoring circuit built into the red laser diode 240, there may be some circumstances in which the power monitoring circuit erroneously believes that insufficient power is being supplied to the red laser diode 240 and responds by increasing the power supplied to the red laser diode 240, thereby causing the red laser diode 240 to exceed the maximum output power (P) associated with the particular laser classification of the red laser diode 240. 2 ). However, as long as the power supplied to the red laser diode 240 is not higher than P 2 , it is possible to allow the red laser diode 240 to continue to be used.

[0086] If the measured slope efficiency of the red laser diode 240 falls within the fourth region 910, the measured slope efficiency of the red laser diode 240 is higher than expected (eg, higher than the minimum expected slope efficiency (S max )). If this situation is caused by a fault in the power monitoring circuit associated with the red laser diode 240, this fault may cause the red laser diode 240 to emit less laser light than expected. However, this may not cause an eye safety issue, so although a warning condition may be indicated, use of the red laser diode 240 may still be permitted.

[0087] The techniques discussed above for performing safety testing on a red laser diode based on slope efficiency are advantageous for a variety of reasons. For example, performing safety testing based on slope efficiency may be less susceptible to variations in performance characteristics between diodes because the slope efficiency check is based on performance characteristics of the red laser diode 240 characterized during calibration of the surgical laser system 202 (e.g., a step performed during the manufacturing process of the surgical laser system 202). In addition, these techniques account for and correct for the effects of aging and temperature differences between calibration and future use of the surgical laser system 202. For example, these techniques may be less susceptible to small uncertainties in diode temperature because slope efficiency depends only weakly on temperature. In addition, safety testing performed using the techniques presented herein is quick to perform, does not interfere with run-time operations, and provides a high degree of confidence that the red laser diode 240 is safe for use during run-time operations.

[0088] Fig.10 An exemplary diagram showing how the various components of ophthalmic surgical device 1000 communicate and operate together is shown. In some embodiments, ophthalmic surgical device 1000 may include Figure 2A surgical laser system 202 is depicted that performs a process 400 for performing safety testing on a laser diode, such as the red laser diode 240 .

[0089] As shown in the figure, the ophthalmic surgical device 1000 includes but is not limited to a surgical laser system 1002, a display 1004, an interconnect 1006, and at least one I / O (input / output) device interface 1008, which can allow various I / O devices (for example, a keyboard, a display, a mouse device, a pen input, etc.) to be connected to the ophthalmic surgical device 1000.

[0090] Further, as shown, the surgical laser system 1002 (which may be Figure 2 The example of the surgical laser system 202 in FIG. 1 may include, but is not limited to, a temperature sensor 1010, a power module 1012, a red laser diode 1014, a central processing unit (CPU) 1016, and a memory 1018. The surgical laser system 1002 may also include other components, such as Figure 2 Those components shown in and described with respect to that figure.

[0091] In some cases, temperature sensor 1010 can be configured to measure an operating temperature of ophthalmic surgical device 1000. Further, in some cases, power module 1012 can be configured to output a plurality of different current levels and apply the plurality of different current levels to an input of red laser diode 1014. Further, in some cases, power module 1012 can be configured to determine a plurality of different output power levels associated with red laser diode 1014 based on the plurality of different current levels applied to the input of red laser diode 1014. In some cases, the plurality of different output power levels include a different output power for each of the plurality of different current levels.

[0092] In some cases, to determine a plurality of different output power levels associated with the laser diode, power module 1012 may be further configured to measure a plurality of output voltage levels associated with red laser diode 1014, each different one of the plurality of output voltage levels corresponding to a different one of a plurality of different current levels applied to an input of red laser diode 1014. Power module 1012 may then be configured to convert the plurality of output voltage levels into a plurality of different output power levels based on the plurality of different current levels applied to the input of red laser diode 1014.

[0093] In some cases, CPU 1016 may include one or more processors that may be configured to obtain a measured temperature of ophthalmic surgical device 1000 from temperature sensor 1010. CPU 1016 may also be configured to obtain from power module 1012 an indication of a plurality of different output power levels and a plurality of different current levels.

[0094] In some cases, the CPU 1016 can be further configured to determine a measured slope efficiency of the red laser diode 1014 based on a plurality of different current levels and a plurality of different output power levels. In some cases, to determine the measured slope efficiency of the laser diode, the CPU 1016 can be further configured to determine a first difference between the plurality of different output power levels, determine a second difference between the plurality of different current levels, and determine a ratio of the first difference to the second difference. In such a case, the measured slope efficiency includes the determined ratio.

[0095] In some cases, the CPU 1016 may be further configured to determine the expected slope efficiency of the red laser diode 1014 based on a measured operating temperature of the ophthalmic surgical device. In some cases, the CPU 1016 may be further configured to determine the expected slope efficiency of the red laser diode 1014 based further on a calibration temperature associated with when the red laser diode 1014 was initially calibrated for the ophthalmic surgical device 1000, a calibration slope efficiency associated with when the red laser diode 1014 was initially calibrated for the ophthalmic surgical device 1000, and one or more aging correction factors. In some cases, indications of the calibration temperature, the calibration slope efficiency, and the one or more aging correction factors may be stored in the memory 1018.

[0096] In some cases, CPU 1016 may be further configured to determine the expected slope efficiency of the laser diode according to: S(t, T) = S cal ·(1+C)+(1+R)·S o '·(TT cal ), where S(t, T) is the expected slope efficiency of the red laser diode 1014 at time t and measured operating temperature T, S cal is the calibration slope efficiency associated with the red laser diode 1014, C is the calibration slope efficiency S cal The first aging correction factor, S o ′ is the slope of the calibration slope efficiency, R is the slope efficiency S used to calibrate the slope o ' is the second aging correction factor, and T cal is the calibration temperature associated with the red laser diode 1014. In some cases, the slope of the calibration slope efficiency (S o′) can also be stored in the memory 1018.

[0097] In some cases, CPU 1016 can be further configured to determine the result of the safety test of red laser diode 1014 based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode. In some cases, CPU 1016 can be further configured to output an electrical signal indicating the result of the safety test of the laser diode. In some cases, display 1004 can be configured to receive the electrical signal from CPU 1016 and display the result of the safety test.

[0098] In some cases, CPU 1016 can be further configured to determine a range of expected slope efficiencies for the red laser diode 1014, the range of expected slope efficiencies for the laser diode comprising a certain number of standard deviations above and below the expected slope efficiency for the red laser diode 1014. In some cases, the certain number of standard deviations comprises two or three standard deviations.

[0099] In some cases, to determine the result of the safety test of the red laser diode 1014, the CPU 1016 may be further configured to determine whether the measured slope efficiency of the red laser diode 1014 is consistent with a range of expected slope efficiencies for laser diodes.

[0100] In some cases, when the measured slope efficiency of the red laser diode 1014 is consistent with the range of expected slope efficiencies for the laser diode, the electrical signal output by the CPU 1016 indicates that the red laser diode 1014 passes the safety test.

[0101] In some cases, when the measured slope efficiency of the red laser diode 1014 is inconsistent with the range of expected slope efficiencies of the red laser diode 1014, and when the measured slope efficiency of the red laser diode 1014 is less than a safety threshold associated with the red laser diode 1014, the electrical signal output by the CPU 1016 indicates that the red laser diode 1014 has failed the safety test. In some cases, the red laser diode 1014 may be associated with a particular laser classification for performing ophthalmic surgery. In some cases, the safety threshold includes a ratio of a maximum output power associated with the particular laser classification and a maximum output power associated with the red laser diode 1014. In some cases, the maximum output power associated with the particular laser classification and the maximum output power associated with the red laser diode 1014 may be stored in the memory 1018.

[0102] In some cases, when the measured slope efficiency of the red laser diode 1014 is inconsistent with the range of expected slope efficiencies of the red laser diode 1014, and when the measured slope efficiency of the red laser diode 1014 is greater than or equal to a safety threshold associated with the red laser diode 1014, the electrical signal output by the CPU 1016 indicates a warning condition associated with the safety test of the red laser diode 1014.

[0103] In some cases, CPU 1016 can retrieve and execute programming instructions stored in memory 1018 for performing Figure 4 The processes described herein and other operations described herein for performing safety testing of laser diodes of ophthalmic surgical equipment. Similarly, CPU 1016 can retrieve and store application data present in memory 1018. Interconnect 1006 transmits programming instructions and application data between CPU 1016, at least one I / O device interface 1008, display 1004, memory 1018, power module 1012, temperature sensor 1010, red laser diode 1014, etc. CPU 1016 can represent a single CPU, multiple CPUs, a single CPU with multiple processing cores, etc. In addition, in some embodiments, memory 1018 can include volatile memory (e.g., random access memory). In addition, in some embodiments, memory 1018 can also include non-volatile memory (e.g., disk drive). Although shown as a single unit, memory 1018 can be a combination of fixed storage devices or removable storage devices, such as a fixed disk drive, a removable memory card or an optical storage device, a network attached storage (NAS) or a storage area network (SAN).

[0104] Example Embodiments

[0105] Implementation examples are described in the following numbered clauses:

[0106] Embodiment 1: A device for performing safety testing on a laser diode of an ophthalmic surgical device, comprising: a temperature sensor, the temperature sensor being configured to measure an operating temperature of the ophthalmic surgical device; a power module, the power module being configured to: output a plurality of different current levels; apply the plurality of different current levels to an input terminal of the laser diode; and determine a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to the input terminal of the laser diode, wherein the plurality of different output power levels include a different output power for each different current level of the plurality of different current levels; one or more processors, The one or more processors are configured to: obtain a measured operating temperature of the ophthalmic surgical device from the temperature sensor; obtain indications of the multiple different output power levels and the multiple different current levels from the power module; determine a measured slope efficiency of the laser diode based on the multiple different current levels and the multiple different output power levels; determine an expected slope efficiency of the laser diode based on the measured operating temperature of the ophthalmic surgical device; determine a result of a safety test of the laser diode based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode; and output an electrical signal indicative of the result of the safety test of the laser diode.

[0107] Embodiment 2: The apparatus of embodiment 1, wherein, in order to determine the plurality of different output power levels associated with the laser diode, the power module is further configured to: measure a plurality of output voltage levels associated with the laser diode, each different output voltage level of the plurality of output voltage levels corresponding to a different current level of the plurality of different current levels applied to an input terminal of the laser diode, and convert the plurality of output voltage levels into the plurality of different output power levels based on the plurality of different current levels applied to the input terminal of the laser diode.

[0108] Embodiment 3: The apparatus of any one of Embodiments 1 to 2, wherein, in order to determine a measured slope efficiency of the laser diode, the one or more processors are further configured to: determine a first difference between the multiple different output power levels, determine a second difference between the multiple different current levels, and determine a ratio of the first difference to the second difference, wherein the measured slope efficiency includes the determined ratio.

[0109] Embodiment 4: A device as described in any of Embodiments 1 to 3, wherein the one or more processors are further configured to determine the expected slope efficiency of the laser diode based on a calibration temperature associated with when the laser diode was initially calibrated for the ophthalmic surgical device, a calibration slope efficiency associated with when the laser diode was initially calibrated for the ophthalmic surgical device, and one or more aging correction factors.

[0110] Embodiment 5: The apparatus of Embodiment 4, wherein the one or more processors are further configured to determine the expected slope efficiency of the laser diode according to: S(t, T)=S cal ·(1+C)+(1+R)·S o '·(TT cal ), where S(t, T) is the expected slope efficiency of the laser diode at time t and measured operating temperature T, S cal is the calibration slope efficiency associated with the laser diode, C is the calibration slope efficiency S cal The first aging correction factor, S o ′ is the slope of the calibration slope efficiency, R is the calibration slope efficiency S o ' is the second aging correction factor, and T cal is the calibration temperature associated with the laser diode.

[0111] Embodiment 6: The apparatus of any one of Embodiments 1 to 5, wherein the one or more processors are further configured to determine a range of expected slope efficiencies of the laser diode, the range of expected slope efficiencies of the laser diode comprising a certain number of standard deviations above and below the expected slope efficiency of the laser diode.

[0112] Embodiment 7: The apparatus of embodiment 6, wherein the certain number of standard deviations comprises two or three standard deviations.

[0113] Embodiment 8: A device as described in any of Embodiments 6 to 7, wherein, in order to determine the result of the safety test of the laser diode, the one or more processors are further configured to determine whether the measured slope efficiency of the laser diode is consistent with the range of expected slope efficiency of the laser diode.

[0114] Embodiment 9: The apparatus of Embodiment 8, wherein when the measured slope efficiency of the laser diode is consistent with a range of expected slope efficiency of the laser diode, the electrical signal output by the one or more processors indicates that the laser diode passes the safety test.

[0115] Embodiment 10: A device as described in any of Embodiments 8 to 9, wherein, when the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiency of the laser diode, and when the measured slope efficiency of the laser diode is less than a safety threshold associated with the laser diode, the electrical signal output by the one or more processors indicates that the laser diode has failed the safety test.

[0116] Embodiment 11: The apparatus of embodiment 10, wherein, when the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiency of the laser diode, and when the measured slope efficiency of the laser diode is greater than or equal to the safety threshold associated with the laser diode, the electrical signal output by the one or more processors indicates a warning condition associated with the safety test of the laser diode.

[0117] Embodiment 12: The apparatus of any one of Embodiments 10 to 11, wherein the laser diode is associated with a specific laser classification for performing ophthalmic surgery, and the safety threshold comprises a ratio of a maximum output power associated with the specific laser classification and a maximum output power associated with the laser diode.

[0118] Embodiment 13: The device of any one of Embodiments 10 to 12, wherein the one or more processors are further configured to disable the laser diode in response to the failed safety test.

[0119] Embodiment 14: A method for performing a safety test on a laser diode associated with an ophthalmic surgical device, comprising: measuring an operating temperature of the ophthalmic surgical device; outputting a plurality of different current levels and applying the plurality of different current levels to an input end of the laser diode; determining a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to the input end of the laser diode, wherein the plurality of different output power levels include a different output power for each different current level of the plurality of different current levels; determining a measured slope efficiency of the laser diode based on the plurality of different current levels and the plurality of different output power levels; determining an expected slope efficiency of the laser diode based on a measured operating temperature of the ophthalmic surgical device; determining a result of the safety test of the laser diode based on the measured slope efficiency of the laser diode and the expected slope efficiency of the laser diode; and outputting an electrical signal indicating the result of the safety test of the laser diode.

[0120] Embodiment 15: A method as described in Embodiment 14, wherein determining the multiple different output power levels associated with the laser diode includes: measuring a plurality of output voltage levels associated with the laser diode, each different output voltage level of the multiple output voltage levels corresponding to a different current level of the multiple different current levels applied to the input terminal of the laser diode, and converting the multiple output voltage levels into the multiple different output power levels based on the multiple different current levels applied to the input terminal of the laser diode.

[0121] Embodiment 16: A method as described in any one of Embodiments 14 to 15, wherein determining the measured slope efficiency of the laser diode includes: determining a first difference between the multiple different output power levels, determining a second difference between the multiple different current levels, and determining a ratio of the first difference to the second difference, wherein the measured slope efficiency includes the determined ratio.

[0122] Embodiment 17: A method as described in any of Embodiments 14 to 16, wherein determining the expected slope efficiency of the laser diode is further based on a calibration temperature associated with when the laser diode was initially calibrated for the ophthalmic surgical device, a calibration slope efficiency associated with when the laser diode was initially calibrated for the ophthalmic surgical device, and one or more aging correction factors.

[0123] Embodiment 18: The method of Embodiment 17, wherein determining the expected slope efficiency of the laser diode comprises determining the expected slope efficiency of the laser diode according to: S(t, T)=S cal ·(1+C)+(1+R)·S o '·(TT cal ), where S(t, T) is the expected slope efficiency of the laser diode at time t and measured operating temperature T, S cal is the calibration slope efficiency associated with the laser diode, C is the calibration slope efficiency S cal The first aging correction factor, S o ′ is the slope of the calibration slope efficiency, R is the calibration slope efficiency S o ' is the second aging correction factor, and T cal is the calibration temperature associated with the laser diode.

[0124] Embodiment 19: The method of any one of Embodiments 14 to 18 further comprises determining a range of expected slope efficiencies of the laser diode, the range of expected slope efficiencies of the laser diode comprising a certain number of standard deviations above and below the expected slope efficiency of the laser diode.

[0125] Embodiment 20: The method of embodiment 19, wherein the certain number of standard deviations includes two or three standard deviations.

[0126] Embodiment 21: The method of any one of Embodiments 19 to 20, wherein determining the result of the safety test of the laser diode comprises determining whether a measured slope efficiency of the laser diode is consistent with a range of expected slope efficiencies of the laser diode.

[0127] Embodiment 22: The method of Embodiment 21, wherein when the measured slope efficiency of the laser diode is consistent with the range of expected slope efficiency of the laser diode, the output electrical signal indicates that the laser diode passes the safety test.

[0128] Embodiment 23: A method as described in any one of Embodiments 21 to 22, wherein, when the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiency of the laser diode, and when the measured slope efficiency of the laser diode is less than a safety threshold associated with the laser diode, the output electrical signal indicates that the laser diode has failed the safety test.

[0129] Embodiment 24: A method as described in Embodiment 23, wherein, when the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiency of the laser diode, and when the measured slope efficiency of the laser diode is greater than or equal to the safety threshold associated with the laser diode, the output electrical signal indicates a warning condition associated with the safety test of the laser diode.

[0130] Embodiment 25: A method as described in any of Embodiments 23 to 24, wherein: the laser diode is associated with a specific laser classification for performing ophthalmic surgery, and the safety threshold comprises a ratio of a maximum output power associated with the specific laser classification and a maximum output power associated with the laser diode.

[0131] Embodiment 26: The method of any one of Embodiments 23 to 25, further comprising disabling the laser diode in response to the failed safety test.

[0132] Embodiment 27: An apparatus comprising means for performing the method according to any one of embodiments 14 to 26.

[0133] Embodiment 28: A non-transitory computer-readable medium, the non-transitory computer-readable medium comprising executable instructions, which when executed by a processor of a device causes the device to perform the method according to any one of Embodiments 14 to 26.

[0134] Embodiment 29: A computer program product, the computer program product being embodied on a computer-readable storage medium, the computer program product comprising code for executing the method according to any one of Embodiments 14 to 26.

[0135] Additional considerations

[0136] As used herein, the phrase "at least one of" a list of items refers to any combination of those items, including single members. For example, "at least one of a, b, or c" is intended to cover any combination of a, b, c, ab, ac, bc, and abc, as well as multiples of the same element (e.g., aa, aaa, aab, aac, abb, acc, bb, bbb, bbc, cc, and ccc or any other order of a, b, and c).

[0137] The foregoing description is provided to enable any person skilled in the art to practice the various embodiments described herein. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments. Therefore, the claims are not intended to be limited to the embodiments shown herein, but are to be given the full scope consistent with the language of the claims.

[0138] In the claims, unless otherwise specified, reference to a singular element is not intended to mean "one and only one", but "one or more". Unless otherwise specifically stated, the term "some" refers to one or more. All structural and functional equivalents of the elements of the various aspects described throughout the present disclosure that are known or will be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be covered by the claims. In addition, regardless of whether such disclosure is explicitly recited in the claims, the content disclosed herein is not intended to be committed to the public. According to 35 U.S.C. §112 (f), the elements of any claim will not be interpreted unless the phrase "device for..." is used to expressly recite these elements, or in the case of a method claim, the phrase "step for..." is used to recite these elements. The word "exemplary" is used herein to mean "used as an example, instance, or illustration". Any aspect described as "exemplary" herein is not necessarily interpreted as preferred or advantageous over other aspects.

Claims

1. An apparatus for performing safety testing on a laser diode of an ophthalmic surgical device, comprising: a temperature sensor configured to measure an operating first temperature of the ophthalmic surgical device; A power module, wherein the power module is configured to: Output multiple different current levels; applying the plurality of different current levels to an input of the laser diode; and determining a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to an input of the laser diode, wherein the plurality of different output power levels includes a different output power for each different current level of the plurality of different current levels; One or more processors configured to: obtaining a measured operating temperature of the ophthalmic surgical device from the temperature sensor; obtaining, from the power module, an indication of the plurality of different output power levels and the plurality of different current levels; determining a measured slope efficiency of the laser diode based on the plurality of different current levels and the plurality of different output power levels; determining an expected slope efficiency of the laser diode based on a measured operating temperature of the ophthalmic surgical device; determining a result of a safety test of the laser diode based on a measured slope efficiency of the laser diode and an expected slope efficiency of the laser diode; and An electrical signal indicative of a result of the safety test of the laser diode is output.

2. The device according to claim 1, wherein: To determine the plurality of different output power levels associated with the laser diode, the power module is further configured to: measuring a plurality of output voltage levels associated with the laser diode, each different one of the plurality of output voltage levels corresponding to a different one of the plurality of different current levels applied to an input of the laser diode, and The plurality of output voltage levels are converted to the plurality of different output power levels based on the plurality of different current levels applied to an input of the laser diode.

3. The device of claim 1, wherein: To determine a measured slope efficiency of the laser diode, the one or more processors are further configured to: determining a first difference between the plurality of different output power levels, determining a second difference between the plurality of different current levels, and A ratio of the first difference to the second difference is determined, wherein the measured slope efficiency comprises the determined ratio.

4. The device of claim 1, wherein: The one or more processors are further configured to determine an expected slope efficiency of the laser diode based further on a calibration temperature associated with when the laser diode was initially calibrated for the ophthalmic surgical device, a calibration slope efficiency associated with when the laser diode was initially calibrated for the ophthalmic surgical device, and one or more aging correction factors.

5. The device of claim 4, wherein: The one or more processors are further configured to determine an expected slope efficiency of the laser diode based on: S(t,T)=S cal ·(1+C)+(1+R)·S o ′·(T-T cal ), Where S(t, T) is the expected slope efficiency of the laser diode at time t and measured operating temperature T, S cal is the calibrated slope efficiency associated with the laser diode, C is the calibrated slope efficiency S for cal The first aging correction factor, S′ o is the slope of the calibration slope efficiency, R is the slope for the calibration slope efficiency S′ o The second aging correction factor, and T cal is the calibration temperature associated with the laser diode.

6. The device of claim 1, wherein: The one or more processors are further configured to determine a range of expected slope efficiencies for the laser diode, the range of expected slope efficiencies for the laser diode comprising a number of standard deviations above and below the expected slope efficiency for the laser diode.

7. The device of claim 6, wherein: The certain number of standard deviations includes two or three standard deviations.

8. The device of claim 6, wherein: To determine a result of the safety test of the laser diode, the one or more processors are further configured to determine whether a measured slope efficiency of the laser diode is consistent with a range of expected slope efficiencies of the laser diode.

9. The device of claim 8, wherein: When the measured slope efficiency of the laser diode is consistent with a range of expected slope efficiencies of the laser diode, the electrical signal output by the one or more processors indicates that the laser diode passes the safety test.

10. The device of claim 8, wherein: When the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiencies of the laser diode, and when the measured slope efficiency of the laser diode is less than a safety threshold associated with the laser diode, the electrical signal output by the one or more processors indicates that the laser diode has failed the safety test.

11. The device of claim 10, wherein: When the measured slope efficiency of the laser diode is inconsistent with the range of expected slope efficiencies of the laser diode, and when the measured slope efficiency of the laser diode is greater than or equal to the safety threshold associated with the laser diode, the electrical signal output by the one or more processors indicates a warning condition associated with a safety test of the laser diode.

12. The device of claim 10, wherein: The laser diode is associated with a specific classification of lasers used to perform ophthalmic surgery, and The safety threshold comprises a ratio of a maximum output power associated with the particular laser class and a maximum output power associated with the laser diode.

13. The apparatus of claim 10, wherein: The one or more processors are further configured to disable the laser diode in response to the failed safety test.

14. A method for performing safety testing on a laser diode associated with an ophthalmic surgical device, comprising: measuring an operating temperature of the ophthalmic surgical device; outputting a plurality of different current levels and applying the plurality of different current levels to an input terminal of the laser diode; determining a plurality of different output power levels associated with the laser diode based on the plurality of different current levels applied to an input of the laser diode, wherein the plurality of different output power levels includes a different output power for each different current level of the plurality of different current levels; determining a measured slope efficiency of the laser diode based on the plurality of different current levels and the plurality of different output power levels; determining an expected slope efficiency of the laser diode based on a measured operating temperature of the ophthalmic surgical device; determining a result of a safety test of the laser diode based on a measured slope efficiency of the laser diode and an expected slope efficiency of the laser diode; and An electrical signal indicative of a result of the safety test of the laser diode is output.

15. The method of claim 14, wherein: Determining the plurality of different output power levels associated with the laser diode comprises: measuring a plurality of output voltage levels associated with the laser diode, each different one of the plurality of output voltage levels corresponding to a different one of the plurality of different current levels applied to an input of the laser diode, and The plurality of output voltage levels are converted into the plurality of different output power levels based on the plurality of different current levels applied to an input of the laser diode.

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