JP2023513104A - Long life laser diode package - Google Patents

Abstract

To provide a high power, high brightness solid-state laser system that maintains initial beam characteristics, such as power level, and does not degrade performance or beam quality for at least 10,000 hours of operation. To provide a high-power, high-brightness solid-state laser system containing oxygen in its internal environment and free of siloxane. [Selection drawing] Fig. 8

Description

This application claims the priority benefit of U.S. Provisional Application No. 62/969,541, filed February 3, 2020, and under 35 U.S.C. Claiming benefit of filing date, the entire disclosure of which is hereby incorporated by reference.

The present invention relates to high power laser systems that provide short wavelength laser energy from about 10 nm (nanometers) to about 600 nm, in embodiments typically from about 350 nm to about 500 nm, and also for additive manufacturing. and uses of these systems and laser beams, including the use of subtractive manufacturing, materials processing, and laser welding. The present invention further relates to such laser systems and their use that provide laser beams with excellent beam quality and, in embodiments, maintain high quality, high power laser beams for extended periods of time.

Infrared (IR)-based additive manufacturing systems (having wavelengths greater than 700 nm, especially greater than 1,000 nm) are particularly challenging in terms of both build volume and build speed, and the overall It suffers from several drawbacks of limited efficiency and safety. IR beams are highly reflective to many metals and are therefore difficult and inefficient to couple to metal targets or substrates. Poor bonding can also be difficult to control in the molding or welding process and can pose health and safety risks due to splatter, outgassing, and particle emissions. The large spot size hinders the ability to obtain high resolution of the built part, which is further hampered by poor connectivity and difficulty in controlling the process. Also, these IR systems have a very limited lifetime and their beam quality degrades steadily, sometimes rapidly, over time. This degradation results in downtime, increased repair and replacement costs, and lost production.

This degradation over time seen in current IR systems is also a significant problem for current UV, blue, and green lasers and laser systems.

As used herein, unless otherwise specified, "UV," "ultraviolet," "UV spectrum," "UV portion of the spectrum," and like terms are to be given the broadest meaning, and are to be given the broadest meaning of about It includes light of wavelengths from 10 nm to about 400 nm, and from 10 nm to 400 nm, and all wavelengths within these ranges.

As used herein, unless otherwise specified, the terms “laser diode,” “diode emitter,” “laser diode bar,” “laser diode chip,” and “emitter” and like terms shall have the broadest meaning. should be given. Generally speaking, a laser diode is a semiconductor device that emits a laser beam, and such devices are commonly referred to as edge-emitting laser diodes because the laser light is emitted from the edge of the substrate. Typically, diode lasers with a single emitting area (emitter) are called laser diode chips, while those with a linear array of emitters are called laser diode bars. The areas that emit the laser beam are called "facets".

As used herein, unless otherwise specified, the terms "high power" lasers and laser beams, and like terms, include powers of at least 100 Watts (W) and greater powers, such as 100 Watts to 10 kW (kilowatts). , from about 100 W to about 1 kW, from about 500 W to about 5 kW, from about 10 kW to about 40 kW, from about 5 kW to about 100 kW, and all powers within these ranges as well as higher powers. means and includes beams and systems.

As used herein, unless otherwise specified, the terms "blue laser beam", "blue laser", and "blue" should be given the broadest meaning and generally laser beams, laser beams, lasers Reference is made to systems that provide light sources, such as lasers and diode lasers, that provide and propagate, for example, laser beams or light having wavelengths from about 400 nm to about 495 nm, 400 nm to 495 nm, and all within these ranges. Typically, blue lasers have wavelengths in the range of about 405-495 nm. Blue lasers include wavelengths of 450 nm, about 450 nm, 460 nm, about 460 nm, 470 nm, about 470 nm. Blue lasers can have bandwidths from about 10 pm (picometers) to about 10 nm, about 5 nm, about 10 nm, and about 20 nm, as well as higher and lower values.

As used herein, unless otherwise specified, the terms "green laser beam", "green laser", and "green" should be given the broadest meaning and generally laser beams, laser beams, lasers Reference is made to systems providing a light source, for example lasers and diode lasers, which provide and, for example, propagate a laser beam or light having a wavelength of about 500 nm to about 575 nm. Green lasers include wavelengths of 515 nm, about 515 nm, 532 nm, about 531 nm, 550 nm, about 550 nm. Green lasers can have bandwidths from about 10 pm to about 10 nm, about 5 nm, about 10 nm, and about 20 nm, and greater and lesser values.

As used herein, unless otherwise specified, the terms "high reliability," "high reliability," lasers and laser systems, and similar terms refer to at least 10,000 hours, about 20,000 hours, about 50,000 hours, about 100,000 hours, about 10 hours to about 100,000 hours, 10,000 to 20,000 hours, 10,000 hours to 50,000 hours, 20,000 hours to about 40,000 means and includes lasers having a lifetime of from about 30,000 hours to about 100,000 hours, and all hours within these ranges, as well as greater hours.

As used herein, unless otherwise specified, the terms “lifetime,” “system lifetime,” and “longevity” and like terms mean that the laser power, other characteristics, and both Rated value ("Rated value", "Rated", and "Rated ___" and similar terms shall mean (i) the rated power, other characteristics, and/or of the laser as defined or calculated by the manufacturer; or ii) while remaining at or near a certain percentage (meaning greater than the laser's initial power, other characteristics, and/or both on first use after all calibrations and adjustments have been made); Defined as time. Thus, for example, "80% laser life" is the total operating time during which laser power, other property, or both are maintained at or above 80% of their rated value, i.e., laser power, other property, or the like. Defined as operating time before both drop below 80% of rated value. For example, "50% laser life" is the total operating time during which laser power, other property, or both are maintained at or above 50% of their rated value, i.e., laser power, other property, or both Defined as operating time before falling below 50% of rated value.

As used herein, unless otherwise indicated or clear from the context, the term "lifetime" (when used without numerical or percentage indications) means "80% laser lifetime" and defined as that.

In general, as used herein, the terms "about" and the symbol "~" are subject to ±10% variation or range, experimental or instrumental error associated with obtaining the stated values, unless otherwise specified. , and preferably larger variations or ranges thereof.

As used herein, unless otherwise specified, terms such as "at least," "greater than," also mean "greater than or equal to," i.e., such terms refer to values less than Exclude.

As used herein, room temperature is 25° C. unless otherwise specified. Also, the standard environmental temperature and standard environmental pressure are 25° C. and 1 atmosphere. Unless otherwise specified, all tests, test results, physical properties, and values dependent on temperature, pressure, or both are given at standard ambient temperature and pressure.

As used herein, unless otherwise specified, references to ranges of values, ranges, about "x" to about "y", and similar terms and quantifications refer to separate values within the range. It just serves as an easy way to reference. They thus include each item, feature, value, amount or quantity contained within that range. As used herein, unless otherwise stated, each point and every individual point within a range is included herein as if it were individually listed herein, and is hereby incorporated by reference into the specification. become part.

Prior to the present invention, laser packages with multiple laser diodes, such as multi-die (multi-diode) laser diode packages, suffered from a combination of carbon and silicon contaminants, which greatly reduced lifetime, In addition, the rate of degradation of beam characteristics such as the rate of degradation of output was significantly increased. The art has generally relied on individual packaging of laser diodes in order to minimize contaminants and achieve long life. However, this conventional approach remains inefficient and inexperienced in meeting the demands for the use of these diodes in laser systems, such as current laser applications and even industrial laser applications, high brightness and high power systems. Successful and generally largely unsatisfactory. As the demand for process requirements and the desire for more laser diodes has grown, the shortcomings of this conventional approach have become more pronounced and more problematic. As a result, the problem of laser diode life and beam quality degradation has increased. This problem exists and has increased for UV, blue and green wavelength laser diodes and diode systems.

The background art is intended to introduce various aspects of technology that may be related to embodiments of the invention. As such, the above description in this section provides a framework for a better understanding of the invention and should not be taken as an admission of prior art.

There is a continuing and increasing demand for more reliable, high power blue, green, and other wavelength solid-state lasers and systems for a variety of applications ranging from welding, additive manufacturing, and other materials processing. laser diode systems for various applications. Thus, there is a long-standing and increasing demand, especially for packaging multiple laser diodes in a single container to achieve long life. There is a long-standing and growing demand for longer lifetime laser systems, including blue, green, and other wavelength solid-state laser systems, including laser diodes and diode systems.

The present invention addresses, among other things, these long-standing growing needs through, among other things, the improvements, articles of manufacture, devices, and processes taught and disclosed herein.

Accordingly, laser diodes are provided that can be packaged in a variety of forms as shown in FIGS. 12-17. To achieve long life for these packaged laser diodes, the components and package are properly cleaned and assembled into the package prior to sealing the package to remove silicon and carbon contaminants. Prior to sealing, an oxygen-containing, preferably oxygen-rich environment is introduced into the package to remove residual carbon contaminants and convert them to _CO2 , rendering them harmless to the laser diode.

SUMMARY OF THE INVENTION Accordingly, there is provided a high power, high brightness solid state laser device assembly for integration into a laser system that provides a high quality laser beam for an extended period of time without substantial degradation of the laser beam properties; is: a housing that defines an internal cavity; the internal cavity is isolated from the environment outside the housing; and a solid state device that directs a laser beam from a plane of propagation of the solid state device along the laser beam path. a solid-state device adapted to propagate through a plane of propagation and wherein the laser beam has a power density in the plane of propagation of at least about 0.5 MW/cm ² ; an optical assembly in optical communication with the solid-state device and in the laser beam path. the solid state device and the optical assembly are disposed within an internal cavity within the housing whereby the solid state device and the optical assembly are isolated from the external environment; the housing has a propagation surface of the housing whereby the laser The beam is transmitted from the housing to the external environment along the laser beam path; the propagation surface of the housing is in optical communication with the optical assembly and is on the laser beam path; the laser exiting the propagation surface of the housing The beam is characterized by beam properties that are: (i) a power of at least 100 W; and (ii) a BPP (beam parameter product) of less than 100 mm mrad; and silicon-based contaminants in the internal cavity. source, thereby avoiding the formation of _SiO2 in the internal cavity during operation of the fixed device; thereby avoiding the internal cavity from depositing _SiO2 ; khrs or less.

Further provided is a high power, high brightness solid state laser device assembly for integration into a laser system that provides a high quality blue laser beam for an extended period of time without substantial degradation of laser beam properties, The assembly includes: a housing defining an internal cavity; isolated from the environment outside the housing; and a housing for propagating a plurality of laser beams from a plurality of facets along a plurality of diode laser beam paths. A plurality of diode laser devices, wherein the laser beams have a wavelength in the range of 400 nm to 500 nm; each laser beam has a power density at each facet of at least about 0.5 MW/ ^cm2 . and; an optical assembly in optical communication with each of the diode laser devices and in the laser beam path; comprising collimating optics, such as collimating optics, and beam combining optics; an optical assembly that combines the beams to provide a combined laser beam along the combined laser beam path; the plurality of diode laser devices and the optical assembly are disposed within an internal cavity within housing 526, thereby providing a plurality of laser beams; The diode laser device and optical assembly are isolated from the external environment; the housing has a housing propagation surface by which the combined laser beam is transmitted from the housing to the external environment along the combined laser beam path; in optical communication with the optical assembly and in the combined laser beam path; the combined laser beam emerging from the propagation surface of the housing is characterized by beam characteristics that: (i) have a power of at least 100 W; ii) a BPP of less than 40 mm mrad; and the internal cavity is free of silicon-based contaminant sources so that no _SiO2 is generated within the internal cavity during operation of the multiple diode laser device; The cavities avoid deposition of _SiO2 ; thereby the deterioration of the properties of the coupled beam is less than 2.3%/khrs.

Still further provided is a high power, high brightness solid-state laser assembly for propagating a high quality blue laser beam along the laser beam path for an extended period of time without substantial degradation of the laser beam properties; is: a housing defining an internal cavity; the housing, wherein the internal cavity defines an isolated environment; and a plurality of optically active surfaces, wherein a blue laser beam propagates from the optically active surfaces. a plurality of optically active surfaces disposed within an isolated environment of the interior cavity of the housing; at least one of the optically active surfaces being a solid-state laser; a plurality of optically active surfaces disposed on the device, wherein the laser beam has a power density of at least about 0.5 MW/cm ² at the one or more optically active surfaces; and The internal cavity is free of silicon-based contaminant sources, thereby avoiding the formation of _SiO2 within the internal cavity during operation of the solid-state laser device; the internal cavity has an oxygen-containing gas; _CO2 is generated from carbon-based contaminants within the internal cavity during operation of the device; multiple optically active surfaces thereby avoid the accumulation of carbon and _SiO2 ; The deterioration rate is 2.3%/khrs or less.

Further provided is a high power, high brightness solid state laser device package for integration into a laser system that provides a high quality blue laser beam for an extended period of time without substantial degradation of laser beam properties, is: a housing defining an internal cavity; the internal cavity being isolated from the environment outside the housing; a housing having a window defining a portion of the internal cavity; a solid-state device adapted to propagate along the beam path, the laser beam having a wavelength in the range of 410 nm to 500 nm, the laser beam having a power density in the plane of propagation of at least about 0.5 MW/cm ² ; the window is in optical communication with the solid-state device and in the laser beam path; the solid-state device is disposed within the housing within the internal cavity, the inner surface of the window not being exposed to the external environment; isolates the solid state device and the inner surface of the window from the external environment; whereby the laser beam is transmitted along the laser beam path from the housing through the window to the external environment; the internal cavity contains a silicon-based contaminant source; , thereby avoiding the formation of SiO ₂ within the internal cavity during operation of the solid-state device; thereby avoiding the accumulation of SiO ₂ in the internal cavity; khrs or less; and having a gas in which the inner cavity is at least 1% oxygen; thereby producing _CO2 from carbon-based contaminants within the inner cavity during operation of the multiple diode laser device, which leaves the propagation surface and the inner surface of the window free of carbon deposits.

Also provided are systems and methods having one or more of the following features: no _SiO2 is generated within the internal cavity during operation of the solid state device; whereby _SiO2 is substantially generated during operation of the solid state laser; _{the internal cavity remains free of SiO2 during operation; the internal cavity is free of SiO2 ; thereby} depositing carbon during operation of the solid state device. is not generated within the internal cavity; thereby substantially no carbon deposits are generated during operation of the solid-state laser, and the internal cavity is kept free of carbon deposits; the internal cavity is free of carbon deposits; the system has tens, hundreds, or thousands of laser diodes, and the system emits laser beams at blue wavelengths The system has a laser diode that emits a laser beam at a wavelength of about 500 nm or less; The system has a laser diode that emits a laser beam at a wavelength of about 500 nm to about 10 nm; The BPP of the laser beam is BPP of the laser beam is less than about 50 mm mrad; BPP of the laser beam is less than about 40 mm mrad; BPP of the laser beam is less than about 20 mm mrad; BPP of the laser beam is about 15 mm the system has a laser diode emitting a laser beam at a wavelength of 500 nm to 10 nm; the laser beam has a bandwidth of about 20 nm or less, about 5 nm or less, about 1 nm or less, about 0.5 nm or less, about have a bandwidth from 20 nm to about 0.5 nm, and all bandwidths within these ranges; the laser system has collection optics; the laser system has collimation optics; the laser system has a scanner; The laser system has a diffraction grating; the laser system has reflective optics, the laser system includes a volume Bragg grating (VBG), a Bragg grating, an etalon, a prism, a variable attenuator, a shutter optical fiber, a gradient index lens. , lenses, cylindrical lenses, waveplates, polarizing coupler cubes, monolithic optical coupler assemblies, Raman crystals, doubling crystals, dielectric reflector assemblies, beam pickoff assemblies, power monitoring assemblies; have an oxygen-containing gas so that no _CO2 is produced from carbon-based contaminants within the internal cavity during operation of the solid-state device; thereby the propagating surfaces and optical assemblies of the solid-state device avoid carbon deposits; the internal cavity has a gas containing at least 1% oxygen whereby _CO2 is produced from carbon-based contaminants within the internal cavity during operation of the solid state device; Assembly avoids carbon deposits.

Further provided is a high power, high brightness solid state laser device package for integration into a laser system that provides a high quality blue laser beam for an extended period of time without substantial degradation in laser beam properties, the package comprising: : a housing defining an internal cavity; the internal cavity being isolated from the environment outside the housing; the housing having a window defining a portion of the internal cavity; wherein the laser beam has a wavelength of 410 nm to 500 nm; and the laser beam has a power density in the plane of propagation of at least about 0.5 MW/cm ² ; wherein the window is in optical communication with the solid state device and in the laser beam path; the solid state device is disposed within the housing within the internal cavity and the inner surface of the window is not exposed to the external environment, thereby The solid state device and the inner surface of the window are isolated from the external environment; whereby the laser beam is transmitted along the laser beam path from the housing through the window to the external environment; the internal cavity is free of silicon-based contaminant sources. , thereby avoiding the formation of SiO ₂ within the internal cavity during operation of the solid-state device; thereby avoiding the accumulation of SiO ₂ in the internal cavity; The inner cavity has a gas that is at least 1% oxygen; whereby _CO2 is generated from carbon-based contaminants within the inner cavity during operation of the multiple diode laser device, thereby propagating. The inner surfaces of the faces and windows remain free of carbon deposits.

Further provided is a sealed container for packaging an individual laser diode for providing a laser beam; the sealed container defines an internal cavity and an inner surface; the inner surface is free of silicon contaminants, thereby No _SiO2 is formed during operation of the diode; and the internal cavity contains means to prevent the formation of carbon contaminants on the inner surface.

Also provided is a sealed container for packaging a plurality of individual laser diodes for providing a laser beam, the sealed container defining an internal cavity and an inner surface, the inner surface substantially free of silicon contaminants. , whereby no _SiO2 is formed during operation of the laser diode, and the internal cavity contains means for preventing the formation of carbon contaminants on the inner surface.

Still further provided is a method of operating a sealed container packaging an individual laser diode for propagating a laser beam having beam characteristics defining a rated power and a rated BPP, the sealed container comprising a window; defining an inner cavity and an inner surface; the method includes the steps of: directing the laser beam from the facets of the laser diode through the cavity and out the window for a total operating time of at least 5,000 hours; Propagating away from the sealed container; no _SiO2 is formed on the inner surface of the cavity during laser diode propagation; _CO2 is formed within the internal cavity during laser diode propagation; during operating time In addition, the laser beam maintains at least 80% of its rated power and at least 80% of its rated BPP, thereby minimizing degradation of laser beam properties over operating time.

Additionally provided is a method of operating a sealed container packaging a plurality of laser diodes for propagating a combined laser beam having beam characteristics defining a rated power and a rated BPP, the sealed container comprising a window. , defining an internal cavity and an inner surface; the method includes the steps of: propagating individual laser beams from facets of a laser diode; and individual laser beams to form combined laser beams within the cavity. combining the laser beams and directing the combined laser beams out of the window and away from the sealed container for a total operating time of at least 5,000 hours; no _SiO2 is formed on the inner surface of the; _CO2 is formed in the internal cavity during propagation of the laser diode; during the operating time, the coupled laser beam is at least 80% of its rated power and its rated BPP of at least 80%, so that beam properties are minimally degraded over operating time.

Still further provided are containers, packages, assemblies, and methods having one or more of the following features: the laser beam is a blue laser beam; the laser beam is a green laser beam; a power of 1 W to 10,000 W, about 500 W, or about 1,000 W; the laser beam has a power density of from 0.5 MW/cm ² to 1,000 MW/cm ² , at least about 1 MW/cm ² , at least about 5 MW/cm ² , or at least about 10 MW/cm ² ; on the inner surface A means for preventing the formation of carbon contaminants in is an oxygen-containing atmosphere; an oxygen-containing atmosphere is flowing into and out of the sealed container; a means for preventing the formation of carbon contaminants on the inner surface is such that the inner surface is carbon The sealed container has an 80% laser life of at least 5,000 hours; The sealed container has an 80% laser life of at least 10,000 hours; Has an 80% laser life of 000 hours to 10,000 hours; Degradation rate is 2.5%/khrs or less; Degradation rate is 2.0%/khrs or less; Degradation rate is 1.5 %/khrs; having or using a heat sink, a diode or a plurality of diodes mounted on the heat sink, thereby forming a two-dimensional array of laser diodes; having or using a backplane, the diodes or a plurality of diodes mounted on the backplane; comprising optics for steering the laser beam; the canister being or comprising a TO-9 Can; a power density of at least about 10 MW/cm ² , the laser beam has a power of at least about 2 W and a degradation rate of 2.0%/khrs or less; the power density is at least about 5 MW/cm ² and the laser beam has a power of at least about 1.5 W; a power density of at least about 15 MW/cm ² , a laser beam having a power of at least about 5 W, and a degradation rate of 2.3%/khrs or less; khrs; the interior cavity has an atmosphere comprising at least 10% oxygen; the interior cavity has an atmosphere comprising at least 40% oxygen; the interior cavity has an atmosphere comprising at least 60% oxygen; contaminant sources are selected from the group consisting of siloxanes, polymeric siloxanes, linear siloxanes, cyclic siloxanes, cyclomethicones, and polysiloxanes; selected from the group consisting of hydrogen; silicon contaminants less than 0.01 g, less than 0.001 g, less than 0.0001 g, less than 0.00001 g, or less than 0.000001 g in package or sealed container; The contaminant has less than 0.01 ppm silicon, less than 0.001 ppm silicon, less than 0.0001 ppm silicon, or less than 0.00001 ppm silicon in the package or sealed container; 0%/khrs or less; beam property degradation rate of 1.8%/khrs or less; characterized by having a lifetime of 10,000 hours or greater; by having a lifetime of 30,000 hours or greater. characterized by having a lifetime of 50,000 hours or more; characterized by having a lifetime of 70,000 hours or more; /cm ² to 1,000 MW/cm ² , at least about 1 MW/cm ² , at least about 5 MW/cm ² , or at least about 10 MW/cm ² ; the internal cavity has an atmosphere containing at least 1% oxygen; Has a total operating time of at least 7,500 hours; Has a total operating time of at least 10,000 hours; 80% of rated power is maintained for an additional 2,500 hours of operating time; is operated over a plurality of intermittent duty cycles, each duty cycle defining a duty cycle time interval of operation, the sum of the duty cycle time intervals of operation being equal to the operation time.

1 is a graph of power versus time, providing a degradation curve showing degradation rates in a high power blue laser system; FIG.

FIG. 2 is a graph of an embodiment of improved power output versus time according to the present invention, providing degradation curves showing degradation rates in four different high power blue laser systems;

1 is a schematic diagram of a laser system according to the invention; FIG.

1 is a schematic diagram of a laser system according to the invention; FIG.

1 is a schematic diagram of a laser system according to the invention; FIG.

1 is a schematic diagram of a laser system according to the invention; FIG.

1 is a graph of laser power in watts (percentage) versus operating time (hours) for an embodiment of a laser system in accordance with the present invention;

1 is a graph of laser power (watts) versus operating time (hours) for an embodiment of a laser system in accordance with the present invention;

1 is a schematic diagram of a diode laser showing typical areas where contaminant deposition can occur but is avoided by an extended lifetime laser embodiment in accordance with the present invention; FIG.

1 is a schematic diagram of a diode laser in a package providing extended lifetime according to the present invention; FIG.

1 is a schematic diagram of a diode laser in a package providing extended lifetime according to the present invention; FIG.

1 is a schematic cross-sectional view of an embodiment of a TO-9Can laser diode according to the present invention; FIG.

13 is an illustration of an embodiment of an implementation of the TO-9Can of FIG. 12 in an embodiment of a multi-laser package according to the present invention;

13 is an illustration of an embodiment of an implementation of the TO-9Can of FIG. 12 in an embodiment of a multi-laser package according to the present invention;

1 is a perspective view of an embodiment of a multiple diode laser package in accordance with the present invention; FIG.

15B is a plan view of the package of FIG. 15A; FIG.

15B is a cross-sectional view of the package of FIG. 15A; FIG.

1 is a schematic plan view of a multiple diode laser package according to the present invention; FIG.

16B is a cross-sectional view of the package of FIG. 16A; FIG.

1 is a schematic plan view of a multiple diode laser package according to the present invention; FIG.

17B is a cross-sectional view of the package of FIG. 17A; FIG.

The present invention relates generally to lasers that produce high quality, highly reliable laser beams in the UV, blue, and green wavelength regions.

In embodiments, the present invention relates to lasers, laser packages, and housings that produce high quality, reliable, and long-lived blue laser beams.

In embodiments, a laser system in the wavelength region of about 400 nm to about 500 nm having a lifetime of at least 5,000 hours and a solid state laser package for such a system are provided.

Although this specification focuses primarily on wavelengths of 500 nm, this is by way of example only and the packaging, assembly and cleaning techniques provided include blue, blue-green, green, shorter wavelengths, and It should be understood that it is potentially applicable to laser systems of other wavelengths, especially high brightness and high power systems.

In general, the power output of blue laser diode emitters is usually about 5 W per diode, typically less than 10 W per diode, although higher power is possible. By combining the beams from multiple emitters, eg diodes, a high power blue laser system is obtained. The combination of these blue laser beams can be from single emitters, bars of emitters, and combinations and variations thereof. Laser beams from these emitters are combined, for example, using a combination of spatial, spectral, coherent, and polarizing methods. Examples of these beam combining systems are described in U.S. Patent Publication Nos. 2016/0322777, 2018/0375296, 2016/0067827, 2019/0273365, and 2020/0086388, and Nov. 25, 2019. No. 16/695,090, filed in U.S. Patent Application Serial No. 16/695,090, the entire disclosures of each of which are incorporated herein by reference.

Combining these beams from multiple emitters generally involves the use of passive optical elements such as lenses, mirrors, gratings, waveplates, etc. to collimate and combine the beams. Raman transforms can also be used for beam combining. For many industrial applications such as welding, brazing, or additive manufacturing, high-intensity light sources are required, which are typically placed in close proximity to the laser emitter inside the same package. equipped with a short focal length lens. In the following, components within the package will refer to any elements that form the laser assembly, including functional optical components (lenses, gratings, mirrors, waveplates, windows, etc.), mechanical components (package housings, spacers, etc.). , mounts, etc.), and positioning components (eg, adhesives, solders, mechanical hardware).

Laser diode manufacturers have advanced in the design and manufacture of blue laser diodes to ensure high emitter reliability. Similarly, reliable dielectric coatings are available that match the typical intensity of blue laser diode light sources while providing the desired reflectivity at blue wavelengths. However, prior to the present invention, high power blue laser diode systems have not reached the level of reliability required for industrial use, especially for cost effective use in industrial applications. It has been found that this is typically due to the presence of silicon-based contaminants and carbon-based contaminant sources that are introduced into the system during assembly of the system, which are described below, Deposits form on the active optical surfaces of the system during operation of the laser, degrading laser performance and shortening the life of the laser and laser system.

A limiting factor, in embodiments a major limiting factor, in the lifetime of high power blue laser diode systems relates specifically to the diode, the optical assembly, and the packaging of both the diode and the optical assembly system. Volatile organic compound contaminants such as hydrocarbons or polysiloxanes result from outgassing of adhesives or other materials in the package. Other common sources of contaminants include airborne contaminants present in the environment during the assembly process, residue from storage containers for any parts, and surface contaminants present on tools used in the process. , and surfaces that typically come into contact with any material used in packaging. Generally, it is currently believed that any organic compound with sufficient vapor pressure to produce trace gaseous contaminants within the temperature range associated with normal laser operation is potentially detrimental to laser system reliability. ing. Short wavelengths of blue lasers, and shorter wavelength lasers, are said to allow two-photon processes to efficiently generate reactive species such as atomic oxygen, hydrogen, or ozone within the package. . These reactive species then undergo gas-phase reactions with volatile organic contaminants that cause various solid deposits or laminates on optical surfaces in the beam path, i.e., optically active surfaces, which are Over time, it increases optical losses, reduces system output, and degrades laser beam properties. These deposits and laminates are believed to progressively reduce the life of the system. These deposits and laminates are also believed to be the primary reason systems reach end of life.

Accordingly, embodiments of the present invention, as described and taught herein, minimize, reduce, and avoid these deposits and provide high reliability, low degradation rates, and long life. provide a blue and potentially green laser system with

FIG. 1 shows a graph of power versus time for a typical blue laser system without reducing the amount of silicon contaminants. Thus, the system includes silicon-based contaminant sources and is therefore not without silicon-based contaminant sources. Pi is the initial output 101, which is also the rated value, and Pf is the final output 102, which corresponds to 88.73% of the rated value after about 150 hours of operation.

Compared to the poor performance of the system of FIG. 1, the performance of embodiments of the present invention shows a significant increase in laser lifetime using embodiments of the present invention, as shown in FIG. FIG. 2 shows four plots (lines) of power versus operating time for four lasers 201, 202, 203, 204 according to embodiments of the present invention. At 400 hours, all of these lasers show greater than 98% laser lifetime.

FIG. 3 shows a schematic block diagram of a high power, high brightness blue laser system 300 . System 300 has a collection of laser diodes, eg emitters 301 . Laser diode 301 has various mechanical parts 320 for mounting, positioning and holding the diode. These mechanical parts 320 are physically associated with the base 321 , directly or indirectly, eg, by being attached, fixed, or the like. Base 321 is mechanically associated with cover 322 having an inner surface 323 . Cover 322 is attached to and sealed to base 321 to form a housing 326 that encloses or contains an internal cavity 334 that is isolated from an external environment 335 . There is an optical component 302 that is directly or indirectly physically associated with a further mechanical component 324 that is directly or indirectly associated with the base 321 . Laser diode 301 and optics 302 are contained within an internal cavity 334 that is isolated from the external environment 335 by housing 326 .

Each of the laser diodes has a facet, eg 304 (only one is shown for clarity), through which the blue laser beam propagates. Laser beam 350 travels along laser beam path 350a (it is understood that the laser beam travels along the laser beam path and is therefore coincident with the laser beam path), through optics 302, and into housing 326. window 325 and propagate through it. The laser beam thus propagates through the internal cavity 334 and out of that cavity and into the external environment 335 .

The interior cavities of these embodiments, and thus the environment within the cavities, preferably all surfaces within the cavities, contain silicone-based materials such as siloxanes, polymerized siloxanes, linear siloxanes, cyclic siloxanes, cyclomethicone, and polysiloxanes. No contaminant sources. In particular, in one embodiment, surfaces and connections within the housing that are heated during operation and/or exposed to the laser beam are free of sources of silicon-based contaminants. "None" means that the amount of contaminants present is so small that the amount of silicon (or specific contaminants) released into the internal cavity during operation is negligible, preferably zero. In this way, the reactive oxygen formed during the propagation of the blue laser beam through the internal cavity has substantially no silicon to react with it, thus minimizing the formation of _SiO2 , preferably avoiding the formation of _SiO2 , more preferably not forming _SiO2 , thus minimizing _SiO2 deposits, avoiding _SiO2 deposits, and even more preferably within optically active surface cavities. Do not allow _SiO2 deposits to form on the optically active surface. The amount of silicon-based contaminants is avoided so that little or negligible silicon is available to form SiO ₂ , or below the level at which laser degradation rates can be greater than in embodiments of the system. is reduced to a level as low as below. In general, an optically active surface is any surface that a laser beam touches and is in the laser beam path, including facets, fiber surfaces, mirrors, lenses, windows, propagating surfaces, and transmissive surfaces. sell.

However, the internal cavity of these embodiments, and thus the environment within that cavity, may contain sources of carbon-based contaminants. Therefore, all or most of the carbon-based contaminants need not be removed during assembly, eg, packaging of the laser assembly or system. Such carbon-based contaminants can include, for example, detergents, solvents, lubricants, oils, human fingerprints and oils, and generally other hydrocarbon sources. The internal cavity, in operation, contains gaseous oxygen, a source of gaseous oxygen (eg, a port or passageway in the housing for supplying oxygen to the system during operation), or both. Oxygen forms reactive atomic oxygen when exposed to a blue laser beam, and this reactive oxygen forms gaseous _CO2 by reacting with carbon released from carbon-based pollutant sources. Thus, deposition, deposition, or build-up of carbon on the optically active surfaces within the internal cavity is minimized, preferably avoided, and more preferably prevented.

The internal cavities of these various embodiments are 1% to 100% oxygen, about 5% to about 80% oxygen, about 10% to about 50% oxygen, about 30% to about 80% oxygen, about It can have from 5% to about 30% oxygen, and the atmospheric amount of oxygen present in air (eg, the internal cavity can contain clean dry air). The other gas in the internal cavity can be nitrogen, for example.

The internal cavities of these embodiments have less than 0.01 ppm silicon, less than 0.001 ppm silicon, less than 0.0001 ppm silicon, and lesser amounts of silicon present or available within the internal cavity.

The combination of one and preferably both gaseous oxygen within the internal cavity of the laser assembly and the absence of silicon-based contaminant sources within the internal cavity, with a blue laser beam takes about 5,000 hours to about 100,000 hours. hours, about 10,000 hours to about 90,000 hours, about 5,000 hours to about 50,000 hours, about 30,000 hours to about 70,000 hours, at least about 20,000 hours, at least about 30,000 hours hours, at least about 40,000 hours, at least about 50,000 hours, and longer (and can also be correctly characterized, marketed, and classified as having such a life). ) to provide assembly.

Various embodiments of laser systems or assemblies that have these high reliability, i.e., long lifetimes, utilize blue laser beams (e.g., about 410 nm to about 500 nm, 410 nm to 500 nm, about 405-495 nm, 450 nm, about 450 nm) , 460 nm, about 460 nm, 470 nm, and about 470 nm wavelengths). These blue laser beams range from about 10 pm (picometer) to about 10 nm, about 5 nm, about 10 nm, about 20 nm, about 10 nm to about 30 nm, about 5 nm to about 40 nm, about 20 nm or less, about 30 nm or less, about 15 nm or less, It can have a bandwidth of about 10 nm or less, as well as higher and lower values. These blue laser beams have powers of about 100 W (Watts) to about 100,000 W, about 100 W to about 40,000 W, about 100 W to about 1,000 W, about 200 W, about 250 W, about 500 W, about 1,000 W, about 10 ,000 W, at least about 100 W, at least about 200 W, at least about 500 W, at least about 1,000 W, as well as higher and lower power outputs. For individual diode packages, these laser beams can have powers of about 1 W to about 10 W, about 3 W, about 5 W, about 6 W, and about 10 W or more. These blue laser beams range from about 5 mm mrad to about 50 mm mrad, less than about 40 mm mrad, less than about 30 mm mrad, less than about 20 mm mrad, less than about 15 mm mrad, less than about 10 mm mrad, 20 mm mrad or less, 15 mm mrad or less, and more. It is possible to have large and small values of BPP. For Raman laser-based systems, the BPP of these blue laser beams is less than 5 mm mrad, less than 1 mm mrad, about 0.1 to about 1 mm mrad, about 0.1 to about 0.5 mm mrad, about 0.13 mm. mrad, and about 0.15 mm mrad.

These laser beams for these various embodiments of laser systems and assemblies may have beam characteristics such as power, BBP, bandwidth, or other characteristics of the beam, and one or more and all of these characteristics. combination) of about 2.5%/khrs (about 2.5% per 1,000 hours) or less, about 2.3%/khrs or less, about 2.1%/khrs or less, about 2.0%/khrs or less , about 1.8%/khrs or less, about 2.3%/khrs to about 1.5%/khrs, and greater and lesser amounts. In preferred embodiments, these degradation rates are present at the "rated value" of the properties for the laser, within the lifetime of the laser system, and both. In preferred embodiments, these degradation rates exist throughout the life of the system. In a more preferred embodiment, the laser system will have those lifetimes where the degradation curve, ie the plot of degradation versus time, is flat, ie the rate of degradation is zero. This period of zero degradation can be from 1 hour to 500 hours or more, and can be periods of 10% of life, 20% of life, 30% of life, and more.

These contaminants (silicon-based and carbon-based) are formed when lasers are operated at low and high power over their entire operating range and rated power. Thus, unless otherwise specified, these degradation rates are for operation of the laser at its rated power within its rated operating range, or the normal established operating range for such lasers.

It is believed that there are two major components that contribute to the accumulation of deposits on the optically active surface, thus reducing the lifetime of blue laser systems. These components are carbon and _SiO2 . Conventional thinking has suggested that components that contribute to deposition are reduced or eliminated during assembly and packaging. The present invention defies such convention, however, by increasing the amount of oxygen which can potentially increase the amount of _SiO2 deposits to manage residual hydrocarbon contaminants. In this way, residual hydrocarbon contaminants may be present, but the system avoids, and preferably is not, a risk to the system due to elevated oxygen levels. The amount of siloxane is reduced, preferably eliminated. Thus, one of the components necessary for deposition or deposition of _SiO2 is minimized or eliminated, and the oxygen forms _CO2 instead of solid carbon deposits or deposition materials, thereby reducing hydrocarbon deposits and deposition. It becomes possible to neutralize things. In one embodiment, the amount of hydrocarbon contaminants is preferably minimized and can be substantially eliminated.

Cleanroom assembly and protocols, such as solvent cleaning, extraction, plasma cleaning, etc., that can be used to remove and avoid the presence of silicon-based contaminant sources, carbon-based contaminant sources, and both. A number of different cleaning and assembly techniques and procedures are known. The cleaning and assembly technique is one example of many different such techniques and combinations that have applicability to these laser systems, including blue laser systems, shorter wavelength systems, blue-green and It will have applicability for green laser systems, and high power systems. In embodiments of the assembly processes for the solid state lasers, optical assemblies, laser systems, and combinations and variations thereof, various methods of cleaning and assembling the parts include blue and green laser systems, as well as shorter wavelength systems. can be used to minimize the adverse effects of various contaminant phenomena found on In embodiments, a method of cleaning and assembling optics for blue laser systems and systems with shorter and longer wavelengths to reduce, minimize, or eliminate substances that degrade laser performance over time. used for These assembly processes for such lasers, optical assemblies, and systems address and resolve the reliability shortcomings of conventional systems. For example, in one embodiment, a cleaning method is used to remove silicon-based contaminant sources, and in an embodiment, an operating method is a cleaning method that removes silicon-based contaminants at specific locations on the component at specific steps in the assembly process. , and combinations and variations thereof, to remove targeted contaminants. The cleaning method preferably accommodates solid-state lasers, optical assemblies, laser systems (e.g., lasers and optics), or combinations thereof that have levels of silicon-based contaminants that are undetectable by standard analytical techniques. It is possible to provide an embodiment of a package. Such packages, including subject embodiments and examples, have less than 0.01 g, less than 0.001 g, less than 0.0001 g, less than 0.00001 g, and less than 0.000001 g silicon-based of contaminants. Such packages, including subject embodiments and examples, contain less than 0.1 ppm silicon (as determined by ppm silicon based on the components of the internal cavity environment, e.g., gases contained within the internal environment), less than 0.01 ppm Silicon, less than 0.001 ppm silicon, less than 0.0001 ppm silicon, less than 0.00001 ppm silicon, and less silicon-based contaminants in the inner cavity. These systems and methods can have one or more of the following features: primarily polysiloxane volatile contaminants are removed; the benefits of residual volatile hydrocarbon removal are provided. other operating parameters are selected to remove different contaminants.

In one embodiment of the assembly process, plasma cleaning is used, in particular plasma cleaning removes trace contaminants from the surfaces of components within the package and removes contaminants or particulates, such as greater amounts of this contaminant or Remove fine particles. In one embodiment, plasma cleaning is used in conjunction with a pre-cleaning step, both polar and non-polar pre-cleaning with carefully selected solvents. Preferably, the solvent is chosen such that its polarity matches that of the contaminant of interest. Thus, multiple preclean, cleaning, and plasma cleaning steps are performed, and these steps can be tailored to specific contaminants.

In one embodiment of the assembly process, the system components are heated under reduced pressure for a period of time to accelerate the outgassing of all volatile components and remove residual traces of volatile contaminants. . This preheating step can and preferably is used with other assembly techniques disclosed herein. Operating conditions of temperature and pressure are chosen such that the vapor pressure of the contaminant of interest is higher than the actual pressure in the oven, but is still safe for the parts. This step also ensures that any residue of solvent from the pre-cleaning step is removed from the part.

An embodiment of the assembly process defines a pre-cleaning and cleaning sequence in which it is convenient to measure the polar and non-polar components of the surface free energy of the cleaned parts at various stages of the cleaning process. good. This provides useful information for selecting the appropriate combination of solvents and optimal gas mixtures to target the actual contaminants to be removed. In embodiments, the preferred sequence may differ for different parts of the assembly due to different manufacturing, storage, and handling processes for each part.

In one embodiment of the assembly process, these cleaning techniques are performed immediately prior to or during packaging as an additional or secondary or tertiary cleaning step, such as a final cleaning step. Even with careful cleaning of parts and tools prior to assembly, some contaminants may find their way into the package during integration. This can come, for example, from airborne contaminants present in the assembly area, with outgassing from the curing adhesive being another source of contaminants. Therefore, in one embodiment, a final cleaning of the assembly is performed just prior to sealing the package. The same cleaning methods described herein can be used for individual parts.

A schematic diagram of a laser diode 1000 is shown in FIG. The diode has a transverse guide ridge 1010 , a front facet 1011 , modes 1012 and a vertical confinement layer 1013 . Contaminants formed during operation typically accumulate along the vertical confinement layer 1013 of the laser diode, with the most contaminant deposited in the central region of the mode, typically decreases in the horizontal direction. Embodiments of the system and method provide a system that avoids, minimizes, and preferably prevents this and other deposits and deposits from occurring during operation.

To prevent the intrusion of external contaminants, high power laser systems have typically been sealed in an inert or protective atmosphere, such as an atmosphere containing little or preferably no oxygen. However, this technique has been found to be ineffective for blue laser systems and ineffective in providing long-lived blue laser systems. It is theorized that the conventional use of inert atmospheres is ineffective for blue laser systems and ineffective for green laser systems due to the contaminant dissociation effects described herein. and potential other, both understood and not yet fully understood, phenomena can be seen in the degradation of laser performance during normal operation of these blue and green wavelength laser systems. , is theorized. Also, during operation of these systems, the temperature inside the package rises, which results in outgassing from any component within the assembly, and thus these trace contaminants from hot outgassing can be released into the system. reliability, and in some cases this effect can be very detrimental.

These problems with blue wavelength systems were found and embodiments of the present invention, green laser systems and shorter wavelength systems, are among the most suitable for precision cleaning, assembly, and both cleaning and assembly. Methods and examples of packages or housings for systems such as optical packages (and components within such packages such as solid-state lasers) are provided during the assembly process and to prevent these detrimental processes and laser system degradation from occurring. .

In addition to the build-up of volatile organic contaminants on optical surfaces in the beam path, another problem is the build-up of silicon dioxide ( _SiO2 ) on the surfaces of laser diode facets or other optical components. This silicon dioxide build-up causes a change in the reflectivity of the coating. In some cases, the accumulation of silicon dioxide changes optical properties. A single blue laser diode before collimation has a very strong optical field at the surface of the laser diode itself. The power density at the facets can exceed up to 20 MW/cm ² due to the formation of modal filaments inside the cavity. It has been found and believed that this high power density results in a two-photon reaction that dissociates the atmosphere within the package. Once dissociated, the free oxygen atoms rapidly combine with any free silicon to form _SiO2 in the facets. _SiO2 is similarly deposited on the carbon gettering. This process of forming and depositing _SiO2 can proceed throughout other optical systems, such as collimating optics, but due to much lower power densities that can be on the order of a few kW/ ^cm2 in collimating optics, Although the deposition rate is 1,000 times smaller than facet, this should be considered in packaging, assembly, and cleaning of the system.

Optically active surfaces, such as fiber faces, windows, or facets, through which laser beams of solid-state laser devices of the systems and assemblies propagate are at least about 0.5 MW/cm ² , at least about 1 MW/cm ² (square megawatts per centimeter), at least about 10 MW/cm ² , at least about 20 MW/cm ² , at least about 50 MW/cm ² , at least about 100 MW/cm ² , at least about 500 MW/cm ² , up to about 1,000 MW/cm ² ; It can have a power density of about 10 MW/cm ² to about 100 MW/cm ² , about 5 MW/cm ² to about 20 MW/cm ² , and about 50 MW/cm ² to about 500 MW/cm ² .

Solid-state devices that generate and propagate laser beams can be used in such systems and assemblies. Preferably, the solid state device propagates laser beams having blue, blue-green and green wavelengths. Such solid-state laser devices include, for example, laser diodes, fiber lasers, Raman fiber lasers, and Raman lasers based on crystals (e.g., diamond, KGW, _YVO4 , Ba( _NO3 ) ₂ , etc.), and any one thereof. One or more combinations and variations are possible. The system includes 1, 2, 3, 5, 10, 10s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, 100s, and 1000s with combined beams to provide high power, high brightness laser beams for industrial and other applications. , and thousands of solid state devices.

Although this specification focuses on complete laser systems, for example, solid state laser devices and optical assemblies can be combined or integrated in a single package or housing, the teachings of which do not include optics. It should be understood that stand-alone laser devices, stand-alone optical assemblies without lasers, and combinations and variations thereof are equally applicable. These assemblies can be optically integrated, eg connected, either in the field or prior to shipment, eg by optical fibers with optical connectors.

Embodiments of such laser devices and systems can be used in industrial applications, such as welding parts, such as parts in electronic storage devices.

The process by which power-loss-causing deposits are produced on facets, on other faces of laser diodes, and on other optically active surfaces is caused by a two-photon process, so the process is It can occur regardless of whether it is pulsed or continuous wave driven. The difference between the two modes of operation is the rate of _SiO2 deposition on the facets of the laser diode. Deposition rate is directly proportional to power density and deposition volume is the integral of deposition rate over time. As a result, if deposition proceeds at a rate of 10 μm/khrs, only 1 μm will be deposited per 1,000 hours elapsed when operated at a 10% duty cycle. The deposition rates used here are exemplary only and depend on many other factors, primarily the amount of polysiloxane entrapped within the package.

The comparative example of FIGS. 1 and 2 uses a 60 W class blue laser composed of 20 single-emitter diodes, each of which is collimated by a fast-axis collimation lens so that it can be coupled into the delivery fiber. . The lenses are mounted with UV curable optical epoxy after sub-micron precision positioning. The package is made from gold plated copper components and uses low temperature solder. The lens is mounted on a glass pedestal so that the thermal expansion coefficients are matched. This very simple assembly uses three different types of optical glue, two solders, three different types of glass, and two types of gold-plated copper. The assembly process includes multiple steps with storage containers for various tools and parts, and every step presents an opportunity for surface contamination. Interference between blue light and contaminants therefore leads to rapid degradation of the output from the device over time. This is illustrated in Figure 1, which shows the performance of a typical device over a long-term test, with an expected laser lifetime of only about 200 hours (by definition the time to reach 80% of rated power). based), which is clearly not sufficient for the production process. The curve in Figure 1 shows a very typical degradation rate of -100%/khrs, with a corresponding lifetime of less than 200 hours for the device. Both devices in Figures 1 and 2 had the same amount of oxygen, 60%.

It has been found that there is at least two interferences of blue light within the system that adversely affect laser performance, particularly laser performance, over time. First, scattered light, reflected light, and both from the system heat the surfaces of the system, increasing outgassing from those surfaces and increasing the amount of contaminants that volatilize, which causes the contaminants to accumulate. increasing the amount of degrades the performance of the laser system. Next is oxygen photolyzed by a laser beam and a two-photon process. Oxygen atoms react with organics in the package to form _CO2 and with polysiloxane to form _SiO2 . In the case of organics, _CO2 does not deposit on any surfaces, so hydrocarbon sources are less of a concern, but polysiloxanes are very detrimental to reliability. As a result, the packaging environment (e.g., the internal environment of the housing containing the solid-state laser device, beam path, and optics) is introduced with water vapor and other contaminants to achieve reliable operation. assembled and sealed to prevent

FIG. 2 shows a graph of the change in output from five samples of high power blue laser devices packaged and assembled to have an oxygen atmosphere without siloxane in the internal environment. The laser device used in the test of FIG. 2 was cleaned using an example cleaning sequence according to this embodiment. The average degradation rate for these devices without siloxane was −2.3%/khrs, which is a 43× lifetime improvement over the device in FIG.

The following examples are provided to illustrate various embodiments of the assembly method, laser system, and operation. These examples are for illustrative purposes, may be prophetic, and should not and should not be viewed as limiting the scope of the invention.

Example 1

FIG. 10 shows a schematic diagram of the laser diode of FIG. 9 assembled in a hermetic package resulting in extended lifetime of the diode. This package can be later integrated into a laser system giving the system an extended lifetime. Diode 1000 is placed inside a hermetic housing 1050 that forms a package or packaging for a laser diode and is a laser diode assembly. Housing 1050 contains an internal environment 1051 that is isolated from an external environment 1052 . Diode 1000 propagates the laser beam along laser beam path 1056 through window 1055 to external environment 1052 . An inner surface 1080 of window 1055 is exposed to and in contact with internal environment 1051 . All surfaces within the inner cavity are free of silicon-based contaminants. The laser beam is in the blue wavelength region and has a power of 3W. The internal environment contains 60% oxygen, whereby _CO2 is produced during operation of the solid-state device from carbon-based contaminants present after cleaning within the internal cavity. The packaged assembly has a power degradation rate of less than 2.0%/khrs and a laser life of at least 30,000 hours.

Example 1A

In the embodiment of Example 1, the internal environment may contain 1% to 80% oxygen. The laser beam power can be from about 1W to about 10W. The power degradation rate can be less than 3%/khrs, less than 2.5%/khrs, less than 2%/khrs, and less than 1.5%/khrs. Embodiments can have laser lifetimes of at least 20,000 hours, at least 40,000 hours, at least 50,000 hours, at least 100,000 hours. In particular, embodiments may have these lifetimes and degradation rates when assembled into a laser system, eg, when packaged with optics.

Example 1B

The laser diode of Example 1 is a TO-9Can blue laser diode, one embodiment of which is shown in FIG.

Example 1C

FIG. 11 shows a schematic diagram of four laser diodes assembled in a hermetic package to provide a blue laser beam that provides extended lifetime of the diodes. This package can be later integrated into the laser system providing the system with extended lifetime. The four laser diodes 1100 a , 1100 b , 1100 c , 1100 d are hermetically packed, eg housed, in a housing 1150 having an internal environment 1151 . Housing 1150 protects and isolates internal environment 1151 from external environment 1152 . The four laser diodes propagate blue laser beams with approximately 5 W of power traveling along beam paths 1156a, 1156b, 1156c, 1156d. Laser beams travel along each beam path from housing 1150 through window 1155 and into the external environment 1152 . An inner surface 1180 of the window 1155 is exposed and in contact with the internal environment 1151 . Four partitioned windows can be used, one window for each diode. All surfaces of the inner cavity are free of silicon-based contaminants. The laser beams are each in the blue wavelength region and have a power of about 5 W each. The internal environment contains 60% oxygen, whereby _CO2 is produced within the internal cavity during operation of the solid-state device from carbon-based contaminants left after cleaning. The packaged assembly has a power degradation rate of less than 2.0% and a laser life of at least 30,000 hours.

Example 1D

In the embodiment of Example 1C, the internal environment contains 1% to 80% oxygen. The laser beam power can be from about 1W to about 10W. The power degradation rate can be less than 3%/khrs, less than 2.5%/khrs, less than 2%/khrs, and less than 1.5%/khrs. Embodiments can have laser lifetimes of at least 20,000 hours, at least 40,000 hours, at least 50,000 hours, and at least 100,000 hours. In particular, embodiments may have these lifetimes and degradation rates when assembled into a laser system, eg, when packaged with optics.

Example 1E

The laser diode of Example 1C is a TO-9Can blue laser diode, one embodiment of which is shown in FIG.

Example 2

FIG. 4 shows an embodiment of a high power, high brightness solid state laser assembly 400 or laser system for providing a high quality laser beam 450 over time without substantial degradation of laser beam properties. and the assembly includes: a housing 426 defining an interior cavity 434; the interior cavity being isolated from the environment 435 outside the housing; a solid state device 401 for propagating along 450a, wherein the laser beam has a power density at the propagation plane 404 of at least about 0.5 MW/cm ² ; a laser in optical communication with the solid state device 401; an optical assembly 402 on the beam path 450a, the solid state device and the optical assembly being disposed within an internal cavity 434 within the housing 426, thereby isolating the solid state device and the optical assembly from the external environment 435; has a housing propagation surface 425 by which the laser beam 450 travels from the housing 426 to the external environment 435 along a laser beam path 450a; 450a; the laser beam emerging from the housing propagation surface is characterized by beam properties that: (i) have a power of at least 100 W; (ii) have a BPP of less than 40 mm mrad; There are no silicon-based contaminant sources, so that no _SiO2 is generated within the internal cavity during _operation of the solid-state device; less than 2.3%/khrs.

Example 3

In one embodiment, the laser assembly of Example 2 has a solid state device that produces a laser beam having a wavelength in the range of 410 nm to 500 nm.

Example 4

In one embodiment, the laser assembly of Example 2 has a solid state device that produces a laser beam having a wavelength in the range of 405 nm to 575 nm.

example 5

In one embodiment, the laser assembly of Example 2 has a solid state device that produces a laser beam having a wavelength in the range of 500 nm to 575 nm.

Example 6

In the laser assembly embodiments of Examples 2, 3, 4 and 5, the solid state device is a Raman fiber laser, a diode laser, a crystal-based Raman laser, and combinations and variations of one or more of these. The optical assembly has optical elements such as collimating optics, focusing optics, lenses, mirrors, beam combining optics, and combinations and variations of one or more of these. The beam characteristics further have a bandwidth of about 20 nm or less. Housing propagation surfaces are window and fiber surfaces, and combinations and variations of one or more of these. The BPP is less than about 15 mm mrad and the power density at the propagating plane is about 1 MW/cm ² to about 1,000 MW/cm ² .

Example 7

In the laser assembly embodiments of Examples 2, 3, 4, 5 and 6, the power of the laser beam is from about 100W to about 1,000W. The beam properties further have a bandwidth of less than about 20 nm, a power density at the plane of propagation from about 0.5 MW/cm ² to about 1,000 MW/cm ² , and a beam property degradation rate of 2.0%/cm2. khrs.

Example 8

In the laser assembly embodiments of Examples 2-7 and 13-26, the internal cavity has a gas consisting of at least 1% oxygen, and CO ₂ is removed from carbon-based contaminants within the internal cavity during operation of the solid state device. is produced, thereby leaving the propagating surfaces of solid-state devices and optical assemblies free of carbon deposits.

Example 9

In the laser assembly embodiments of Examples 2-7 and 13-26, the internal cavity has a gas consisting of at least 5% oxygen, and CO ₂ is removed from carbon-based contaminants within the internal cavity during operation of the solid state device. is produced, thereby leaving the propagating surfaces of solid-state devices and optical assemblies free of carbon deposits.

example 10

In the laser assembly embodiments of Examples 2-7 and 13-26, the internal cavity has a gas consisting of at least 10% oxygen, and CO ₂ is removed from carbon-based contaminants within the internal cavity during operation of the solid state device. is produced, thereby leaving the propagating surfaces of solid-state devices and optical assemblies free of carbon deposits.

Example 11

In the laser assembly embodiments of Examples 2-7 and 13-26, the internal cavity has a gas consisting of at least 20% oxygen, and CO ₂ is removed from carbon-based contaminants within the internal cavity during operation of the solid state device. is produced, thereby leaving the propagating surfaces of solid-state devices and optical assemblies free of carbon deposits.

Example 12

In the laser assembly embodiments of Examples 2-7 and 13-26, the internal cavity has a gas comprising from about 5% to at least about 50% oxygen, and a carbon-based gas within the internal cavity during operation of the solid state device. _CO2 is produced from the contaminants so that the propagating surfaces of solid state devices and optical assemblies remain free of carbon deposits.

Example 13

In the laser assembly embodiments of Examples 2-12 and 17-26, the rate of beam property degradation is less than or equal to 2.0%/khrs, from 2.0%/khrs to 1%/khrs.

Example 13A

The degradation rate of Example 13 is maintained for 5,000 hours life, 7,000 hours life, and 10,000 hours life.

Example 14

In the laser assembly embodiments of Examples 2-12 and 17-26, the rate of beam property degradation is less than or equal to 1.8%/khrs, from 1.8%/khrs to 0.8%/khrs.

Example 14A

The degradation rate of Example 14 is maintained for 5,000 hours life, 7,000 hours life, and 10,000 hours life.

example 15

In the laser assembly embodiments of Examples 2-12 and 17-26, the assembly has and is characterized as having an extended lifetime of 10,000 hours or more.

Example 16

In the laser assembly embodiments of Examples 2-12 and 17-26, the assembly has and is characterized as having an extended lifetime of 5,000 hours or more.

Example 17

FIG. 5 shows a schematic diagram of a high power, high brightness solid state laser assembly 500 for delivering a high quality blue laser beam 550 for an extended period of time without substantial degradation of laser beam properties. The assembly includes; a housing 526 defining an interior cavity 534, the interior cavity being isolated from the environment 535 outside the housing 526; and a plurality of facets, e.g. along 550 a plurality of laser beams, for example a plurality of diode laser devices 501a, 501b, 501c, 501d, 501e for propagating beams 550, the laser beams having wavelengths in the range of 400 nm to 500 nm; a plurality of diode laser devices, each laser beam having a power density of at least about 0.5 MW/cm ² at each facet; and an optical assembly 502 in optical communication with each of the diode laser devices and in the laser beam path. has collimating optics, such as collimating optics 560, and beam combining optics 565; combines a plurality of diode laser beams to provide a combined laser beam 552 along combined laser beam path 552a. , an optical assembly 502; a plurality of diode laser devices and optical assemblies disposed within an internal cavity 534 within a housing 526, thereby isolating the plurality of diode laser devices and optical assemblies from an external environment 535; The housing has a housing propagation surface 525 by which the combined laser beam is transmitted from the housing 526 to the external environment 535 along a combined laser beam path 552a; and on the combined laser beam path 552a; the combined laser beam 552 exiting the housing propagation surface 525 is characterized by beam characteristics that are: (i) a power of at least 100 W; the internal cavity 534 is free of silicon-based contaminant sources so that no _SiO2 is generated within the internal cavity during operation of the multiple diode laser device; ₂ remains free of deposits; whereby the degradation rate of the coupled beam properties is less than 2.3%/khrs.

Example 18

In the laser assembly embodiments of Example 17 and other examples, the beam characteristic further has a bandwidth of about 15 nm or less; the housing propagation surface is selected from the group consisting of a window and a fiber surface; less than about 15 mm mrad; and power density at the propagating plane of from about 0.5 MW/cm ² to about 1,000 MW/cm ² .

Example 19

In the laser assembly embodiments of Example 17 and other examples, the beam characteristics further have a bandwidth of about 15 nm or less; the power of the combined laser beam is at least about 500 W; BPP is less than about 30 mm mrad; and power density at the propagating plane is from about 0.5 MW/cm ² to about 1,000 MW/cm ² .

example 20

FIG. 6 illustrates a high power, high brightness solid state laser assembly 600 for providing a high quality blue laser beam 650 along a laser beam path 650a for an extended period of time without substantial degradation of laser beam properties. Schematically shown, the assembly includes: a housing 626 defining an interior cavity 634; the housing, wherein the interior cavity 634 defines an isolated environment; and a plurality of optically active surfaces, such as: Surface 604a, Surface 604b, Surface 604c, Surface 604d, Surface 604e wherein a blue laser beam propagates from, is transmitted into, or is reflected by an optically active surface. a plurality of optically active surfaces disposed within the isolated environment of the housing interior cavity 634; and at least one of the optically active surfaces disposed on the solid state laser device 601. the laser beam has a power density of at least about 0.5 MW/cm ² at one or more optically active surfaces, e.g. the internal cavity 634 is free of silicon-based contaminant sources, so that no _SiO2 is generated within the internal cavity during operation of the solid-state laser device; the internal cavity 634 has an oxygen-containing gas; _CO2 is produced from carbon-based contaminants within the internal cavity during operation of solid-state laser devices; thereby leaving multiple optically active surfaces free of carbon and _SiO2 deposits; The power of the beam has a degradation rate of less than 2.3%/khrs.

Optically active surface 604 e is a window for transmitting laser beam 650 out of the housing and into external environment 635 .

example 21

In laser assembly 600 of FIG. 6 and laser assembly 500 of FIG. 5, the solid-state laser produces a laser beam having a wavelength in the green wavelength region.

Example 21A

The green solid-state laser of Example 22 is an IR laser system doubled with a lithium niobate crystal. The system has a laser diode, an external cavity, and a lithium niobate crystal at the focal point of the external cavity, all contained within a housing.

Example 22

In the laser systems and assemblies of Examples 2-21, 21A, the laser beam is about 5 nm, about 10 nm, about 20 nm, about 10 nm to about 30 nm, about 5 nm to about 40 nm, about 20 nm or less, about 30 nm or less, about 15 nm or less, It has a bandwidth of about 10 nm or less.

example 23

In the laser systems and assemblies of Examples 2-22, the laser beam at or near the point where the beam exits the housing and propagates into the external environment has a power of about 100 W to about 100,000 W, about 100 W to about 40,000 W, about It has a power output of 100 W to about 1,000 W, about 200 W, about 250 W, about 500 W, about 1,000 W, about 10,000 W, at least about 100 W, at least about 200 W, at least about 500 W, and at least about 1,000 W.

example 24

In the laser systems and assemblies of Examples 2-23, the laser beam has a BPP of about 10 mm mrad to about 50 mm mrad, less than about 40 mm mrad, less than about 30 mm mrad, less than about 20 mm mrad, less than about 15 mm mrad, less than about 10 mm mrad. have.

example 25

In the laser systems and assemblies of Examples 2-23, the potential sources of silicon-based contaminants that were eliminated and minimized were siloxanes, polymerized siloxanes, linear siloxanes, cyclic siloxanes, cyclomethicone, polysiloxanes, and are one or more combinations and variations of

Example 26

In the laser systems and assemblies of Examples 2-25, the sources of carbon-based contaminants mitigated by the presence of oxygen within the internal cavity are solvent residues, oils, fingerprints, other sources of hydrocarbons, and one or more of these. are combinations and variations of

Example 27

A fixed high brightness blue laser embodiment is shown in Table 1. This table shows the power, brightness, and performance that can be achieved with a 2.5 Watt laser diode in a two-dimensional spectral beam-combining configuration. This table illustrates how the power and intensity of a laser system based on the building block 350 Watt module is scaled up to multi-kW power levels using a fiber coupler and launched into a process fiber. there is

Table 1

Systems providing the beams of Table 1 are about 5%/khrs to about 1.5%/khrs or less, 2.5%/khrs or less, 2.0%/khrs or less, 1.8%/khrs or less, 1 It has degradation rates for both beam properties in Table 1 that are less than 0.0% and smaller values. Systems that provide Table 1 (both beam characteristics) have been used for at least about 5,000 hours to about 100,000 hours, at least about 5,000 hours, at least about 10,000 hours, at least about 20,000 hours, at least about 40 hours. ,000 hours, about 10,000 hours to about 50,000 hours, and longer.

Example 28

The same modules as in example 27 can also be combined in free space which preserves brightness but slightly complicates module replacement. The power and beam parameter products that can be achieved using free-space coupling are shown in Table 2.

Table 2

Systems providing the beams of Table 2 are about 5% to about 15%/khrs or less, 2.5%/khrs or less, 2.0%/khrs or less, 1.8%/khrs or less, 1.0%/khrs or less. with degradation rates for both beam properties in Table 2 below and below khrs, and smaller values. A system that provides the beams of Table 2 (both beam characteristics) may be used for at least about 5,000 hours to about 100,000 hours, at least about 5,000 hours, at least about 10,000 hours, at least about 20,000 hours, at least It has a life of about 40,000 hours, about 10,000 hours to about 50,000 hours, and longer life.

Example 29

An embodiment of a solid state high brightness blue laser for a system using higher power blue laser diodes with each device being about 6.5 watts is shown in Table 3. The base module is approximately 900 watts and these modules are combined using fiber couplers to build a high power, high brightness blue laser diode system as shown in Table 3.

Table 3

Systems that provide the beams of Table 3 are about 5% to about 1.5%/khrs or less, 2.5%/khrs or less, 2.0%/khrs or less, 1.8%/khrs or less, 1.0 %/khrs, and have degradation rates of both beam properties that are lesser. Systems that provide beams of Table 3 (both characteristics) have been used for at least about 5,000 hours to about 100,000 hours, at least about 5,000 hours, at least about 10,000 hours, at least about 20,000 hours, at least about 40,000 hours, about 10,000 hours to about 50,000 hours life, and longer life.

example 30

FIG. 7 is a graph of laser power versus operating time. It can be seen that the blue laser diode assembly provides an operating profile with a slow degradation rate (plot line 701). The degradation rate has a plateau 702 around 200 to 550 hours. After about 800 hours, the degradation rate is about 0.7%/khrs. This degradation rate, shown between time 703 of 800 and 1,600 hours, remains the same (ie, the slope of the plot line does not change significantly) for the remainder of the system's lifetime.

Example 31

FIG. 8 is a graph of laser power versus operating time. It can be seen that the blue laser diode assembly provides an operating profile with a slow degradation rate (plot line 801). The degradation rate has a plateau from around 150 hours to around 800 hours. After about 800 hours, the degradation rate is about 0.7%/khrs. This degradation rate, shown between times of 800 and 1,600 hours, remains the same (ie, the slope of the plot line does not change significantly) for the remainder of the system's lifetime.

example 32

FIG. 12 is an example of a TO-9Can, a packaged laser diode. In packaging laser diodes, the amount of silicon-based contaminants is reduced and the package is filled with an oxygen-rich atmosphere. The TO-9Can 1200 has stainless steel walls 1201 forming a housing 1205 with a heat sink 1204 . TO-9Can has laser diode 1203 and window 1206 . Housing 1205 is filled with, eg, contains, an oxygen-rich atmosphere.

example 33

Figures 13 and 14 show a standard TO-9 laser diode by mounting multiple TO-9 packages into a suitably machined heat sink capable of holding each individual TO-9 package. It shows how package 1200 is placed into multi-laser packages 1250 and 1250a. Laser diodes mounted in TO-9 packages must be hermetically sealed with minimal silicon and carbon contaminants (which can be minimized), and they must be protected by an oxygen atmosphere. mitigated and managed. Once the laser diode assembly has been properly cleaned, the package 1200 is sealed with an oxygen-rich environment inside the package. Each package is individually sealed to ensure reliable operation.

example 34

FIG. 15 shows a multi-die laser diode package 1501 with 20 individual laser diodes eg 1502 mounted on a copper bar eg 1503 to produce a vertical spatial emission source. Each of the diodes is precision mounted on a copper bar and each bar is precision mounted to the backplane heatsink 1504 . A metal mask 1505 is added to protect the diode from back reflections and to minimize stray or scattered light within the package and window 1506 . The package is cleaned to remove all sources of silicon contaminants and preferably also to remove and reduce carbon contaminant sources. Once the package is sealed, it is filled with an oxygen-rich environment to provide a means for converting free carbon to _CO2 , which is harmless to the laser diode and cannot be dissociated by blue light. The assembly can have a life of greater than 5,000 hours and a life of greater than 10,000 hours.

example 35

FIG. 16 shows a multi-die laser diode package 1600 with twenty individual laser diodes, eg 1607, mounted on a backplane heatsink 1694. FIG. Package 1600 has a reflector, eg, 1606, and a window 1602, through which a laser beam traveling along a laser beam path, eg, 1605 travels. The package is cleaned to remove all silicon contaminant sources and preferably also to remove and reduce carbon contaminant sources. Once the package is sealed, it is filled with an oxygen-rich environment to provide a means for converting free carbon to _CO2 , which is harmless to the laser diode and cannot be dissociated by blue light. The assembly can have a life of greater than 5,000 hours and a life of greater than 10,000 hours.

example 36

FIG. 17 shows a similar method and assembly to that shown in FIG. The package has a window, eg 1702 , through which the laser beam travels along a laser beam path, eg 1705 . A separate hermetic package, eg 1701, and a laser diode, eg 1707, are mounted on a heat sink, eg 1704. FIG. The smaller volume surrounding each laser diode package is easier to clean, reduces the potential for silicon contaminants, and preferably eliminates and reduces carbon contaminant sources, requiring more complex assembly cleaning. can avoid becoming The laser diode and reflector should be cleaned prior to sealing to minimize silicon contaminants and preferably also remove and reduce carbon contaminant sources. Each package, eg 1701, is sealed in an oxygen-rich environment to convert residual carbon to _CO2 , which is harmless to the laser diode. This process results in long life for laser diodes. This assembly can have a lifetime greater than 5,000 hours and a lifetime greater than 10,000 hours.

It is not necessary to provide or address the theory underlying new and innovative processes, materials, performance, other advantages and properties that are the subject of or related to embodiments of the present invention Please note. Nonetheless, various theories are provided herein to further advance the technology in this important area, particularly the important areas of lasers, laser processing, and laser applications. These theories put forth herein in no way limit, limit or narrow the scope of protection conferred on the claimed invention unless expressly stated otherwise. These theories may not be required or practiced to utilize the present invention. The present invention derives new and heretofore unknown theories to explain the operation, function, and features of the embodiments of the methods, articles, materials, devices, and systems of the present invention, and later developed. It should be understood that such theory does not limit the scope of protection given to this invention.

The various embodiments of lasers, diodes, arrays, modules, assemblies, activities and operations described herein can be used in the above fields and various other fields. Additionally, these embodiments can be used with, for example, existing lasers, additive manufacturing systems, operations and activities, and other existing equipment; future lasers, additive manufacturing. Systems, operations, and activities; items as modified in part based on the teachings herein. Also, the various embodiments described herein may be used in various different combinations with each other. For example, configurations provided in various embodiments herein may be used with each other. For example, the components of embodiments having A, A′ and B and the components of embodiments having A″, C and D can be combined in various combinations in accordance with the teachings herein, eg, A, C, D, and A , A″C and D, and so on. Therefore, the scope of protection given to the present invention should not be limited to the particular embodiments, configurations, or arrangements described in the particular embodiments, examples, or embodiments in the particular drawings.

The present invention may be embodied in forms other than those specifically disclosed herein without departing from the spirit or essential characteristics thereof. The described embodiments are to be considered in all respects as illustrative and not restrictive.

Claims (57)

A hermetic container for packaging an individual laser diode for providing a laser beam, the sealed container defining an internal cavity and an inner surface, said inner surface being free of silicon contaminants, whereby said laser diode is free during operation. A sealed container wherein no _SiO2 is formed and said internal cavity includes means for preventing the formation of carbon contaminants on said inner surface. A hermetic container for packaging a plurality of individual laser diodes for providing a laser beam, the sealed container defining an internal cavity and an inner surface, said inner surface being substantially free of silicon contaminants, whereby said laser is A sealed container in which _{no SiO2} is formed during operation of the diode and wherein said internal cavity contains means for preventing carbon contaminants from forming on said inner surface. 3. The sealed container according to claim 1 or 2, wherein said laser beam is a blue laser beam. 3. The sealed container according to claim 1 or 2, wherein said laser beam is a green laser beam. 5. The sealed container of any one of claims 1-4, wherein the laser beam has a power of 1W to 10,000W, about 500W, or about 1,000W. 6. The sealed container of any one of claims 1-5, wherein the laser beam has a BPP of 50 mm mrad to 10 mm mrad, 20 mm mrad to 1 mm mrad, or 10 mm mrad to 0.1 mm mrad. 2. The laser beam of claim 1, wherein the laser beam has a power density of 0.5 MW/ ^cm2 to 1,000 MW/ ^cm2 , at least about 1 MW/ ^cm2 , at least about 5 MW/ ^cm2 , or at least about 10 MW/ ^cm2 . 7. The sealed container according to any one of 6. 7. A sealed container according to any preceding claim, wherein said means for preventing the formation of carbon contaminants on said inner surface is an oxygen-containing atmosphere. 9. The sealed container of Claim 8, wherein the oxygen-containing atmosphere has an oxygen concentration of at least 1%, at least 10%, at least 20%, at least 50%, or from 5% to 80%. 10. The sealed container according to claim 8 or 9, wherein the oxygen-containing atmosphere flows into and out of the sealed container. 7. Any one of claims 1 to 6, wherein the means for preventing the formation of carbon contaminants on the inner surface is that the inner surface is free of carbon contaminants. sealed container. 12. The sealed container of any one of claims 1-11, wherein the sealed container has an 80% laser life of at least 5,000 hours. 12. The sealed container of any one of claims 1-11, wherein the sealed container has an 80% laser lifetime of at least 10,000 hours. 12. The sealed container of any one of claims 1-11, wherein the sealed container has an 80% laser lifetime of 5,000 hours to 10,000 hours. 15. The sealed container according to any one of claims 1 to 14, wherein said deterioration rate is 2.5%/khrs or less. 15. The sealed container according to any one of claims 1 to 14, wherein said deterioration rate is 2.0%/khrs or less. 15. The sealed container according to any one of claims 1 to 14, wherein said deterioration rate is 1.5%/khrs or less. 18. A hermetic seal according to any one of the preceding claims, comprising a heat sink, such that the diode or the plurality of diodes is mounted on the heat sink, thereby forming a two-dimensional array of laser diodes. container. 18. A sealed container according to any one of the preceding claims, comprising a backplane, the diode or the plurality of diodes being mounted on the backplane. 20. A sealed container according to any preceding claim, comprising an optical system for manipulating the laser beam. A sealed container according to any preceding claim, wherein the container is or comprises TO-9Can. A high power, high brightness solid-state laser device package for integration into a laser system that provides a high quality blue laser beam for an extended period of time without substantial degradation of the laser beam properties, comprising:
a. a housing defining an internal cavity, the internal cavity being isolated from the environment outside the housing;
b. a housing having a window defining a portion of the internal cavity;
c. A solid-state device adapted to propagate a laser beam from a propagation surface of said solid-state device along a laser beam path, said laser beam having a wavelength in the range of 410 nm to 500 nm, said laser beam a solid-state device having a power density of at least about 0.5 MW/cm ² at
d. the window is in optical communication with the solid state device and in the laser beam path;
e. The solid-state device is disposed within the internal cavity within the housing and the inner surface of the window is not exposed to the external environment, thereby isolating the solid-state device and the inner surface of the window from the external environment. and
f. the laser beam is transmitted along the laser beam path from the propagation surface through the window to the external environment;
g. The internal cavity is free of silicon-based contaminant sources, thereby avoiding the formation of _SiO2 within the internal cavity during operation of the solid state device, thereby preventing the internal cavity from depositing _SiO2 . , whereby the rate of deterioration of the properties of the beam is less than or equal to 2.3%/khrs;
h. The internal cavity has a gas containing at least 1% oxygen, whereby _CO2 is produced from carbon-based contaminants within the internal cavity during operation of the solid-state device to provide a propagating surface of the solid-state device. and wherein the inner surface of said window remains free of carbon deposits. 23. The package of claim 22, wherein said sealed container has an 80% laser life of at least 5,000 hours. 23. The package of claim 22, wherein said sealed container has an 80% laser life of at least 10,000 hours. 23. The package of Claim 22, wherein the sealed container has an 80% laser life of 5,000 hours to 10,000 hours. 23. The package of claim 22, wherein said diode laser is TO-9Can. 27. Any one of claims 22-26, wherein the power density is at least about 10 MW/ ^cm2 , the laser beam has a power of at least about 2 W, and the degradation rate is no greater than 2.0%/khrs. package as described. 27. Any of claims 22-26, wherein the power density is at least about 5 MW/ ^cm2 , the laser beam has a power of at least about 1.5 W, and the degradation rate is no greater than 1.8%/khrs. Package as described in paragraph 1. 27. Any one of claims 22-26, wherein the power density is at least about 15 MW/ ^cm2 , the laser beam has a power of at least about 5 W, and the degradation rate is no greater than 2.3%/khrs. package as described. 30. The package of any one of claims 22-29, having at least 10% oxygen. 30. The package of any one of claims 22-29, having at least 40% oxygen. 30. The package of any one of claims 22-29, having at least 60% oxygen. 33. The package of any one of claims 1-32, wherein the silicon-based contaminant source is selected from the group consisting of siloxanes, polymeric siloxanes, linear siloxanes, cyclic siloxanes, cyclomethicones, and polysiloxanes. . 34. The package or sealed container of any one of claims 1-33, wherein the carbon-based contaminant source is selected from the group consisting of solvent residues, oils, fingerprints, and hydrocarbons. 35. Any of claims 1-34, wherein the silicon contaminant is less than 0.01 g, less than 0.001 g, less than 0.0001 g, less than 0.00001 g, or less than 0.000001 g in the package or sealed container. A package or sealed container according to claim 1. Claims 1-35, wherein the silicon contaminant has less than 0.01 ppm silicon, less than 0.001 ppm silicon, less than 0.0001 ppm silicon, or less than 0.00001 ppm silicon in the package or sealed container. A package or sealed container according to any one of the preceding claims. 37. Any one of claims 1-36, wherein the power density is at least about 10 MW/ ^cm2 , the laser beam has a power of at least about 2 W, and the degradation rate is no greater than 2.0%/khrs. The package or sealed container described in . 38. A package or sealed container according to any one of the preceding claims, wherein said deterioration rate of said beam properties is 2.0%/hkrs or less. 39. A package or sealed container according to any one of the preceding claims, wherein said rate of deterioration of said beam properties is less than or equal to 1.8%/khrs. 40. Package or sealed container according to any one of the preceding claims, characterized in that the assembly has a life span of 10,000 hours or more. 41. Package or sealed container according to any one of the preceding claims, characterized in that the assembly has a life span of 30,000 hours or more. 42. A package or sealed container according to any one of the preceding claims, characterized in that the assembly has a life span of 50,000 hours or more. 43. A package or sealed container according to any one of the preceding claims, characterized in that the assembly has a life span of 70,000 hours or more. A method of operating a sealed container packaging an individual laser diode for propagating a laser beam having beam characteristics defining a rated power and a rated BPP, said sealed container comprising a window and an internal cavity. and defining an inner surface,
The method is
a. allowing the laser beam to propagate from the facets of the laser diode, through the cavity, out the window, and away from the sealed container for an operating time totaling at least 5,000 hours;
b. no _SiO2 is formed on the inner surface of the cavity during propagation of the laser diode;
c. _CO2 is formed within the internal cavity during propagation of the laser diode;
d. such that the laser beam maintains at least 80% of its rated power and at least 80% of its rated BPP during the operating time, such that the properties of the laser beam degrade minimally over the operating time. Done, way. A method of operating a sealed container packaging a plurality of laser diodes for propagating a combined laser beam having beam characteristics defining a rated power and a rated BPP, said sealed container having a window and an interior defining a cavity and an inner surface;
The method is
a. Propagating individual laser beams from the facets of the laser diode and combining the individual laser beams to form the combined laser beams within the cavity have a total of at least 5,000 hours of operation. directing the combined laser beam out of the window and away from the sealed container for a period of time;
b. no _SiO2 is formed on the inner surface of the cavity during propagation of the laser diode;
c. _CO2 is formed within the internal cavity during propagation of the laser diode;
d. such that, during said operating time, said combined laser beam maintains at least 80% of its rated power and at least 80% of its rated BPP, such that said beam characteristics degrade minimally over said operating time. Done, way. 46. A method according to claim 44 or 45, wherein said laser beam is a blue laser beam. 46. A method according to claim 44 or 45, wherein said laser beam is a green laser beam. 48. The method of any one of claims 44-47, wherein the rated power is between 1 W and 10,000, about 500 W power, or about 1,000 W power. 49. The method of any one of claims 44-48, wherein the rated BPP is 50 mm mrad to 10 mm mrad, 20 mm mrad to 1 mm mrad, or 10 mm mrad to 0.1 mm mrad. the laser beam is 0.5 MW/cm ² to 1,000 MW/cm 2 , at least about 1 MW/cm ² , at least about 5 MW/cm ² , or ^at least about 10 MW/cm at the facet, the window, or both; 50. A method according to any one of claims 44 to 49, having a power density of ² . 51. The method of any one of claims 44-50, wherein the internal cavity comprises gaseous oxygen. 52. The method of any one of claims 44-51, wherein the internal cavity has an atmosphere comprising at least 1% oxygen. 53. The method of any one of claims 44-52, wherein the operating time has a total of at least 7,500 hours. 53. The method of any one of claims 44-52, wherein the operating time has a total of at least 10,000 hours. 53. The method of any one of claims 44-52, wherein 80% of the rated power is maintained for an additional 2,500 hours of operating time. 53. The method of any one of claims 44-52, wherein 80% of the rated power is maintained for an additional 5,000 hours of operating time. 45. Said container is operated for a plurality of intermittent duty cycles, each duty cycle defining a duty cycle time interval of operation, said sum of said duty cycle time intervals of operation being equal to said operation time. 57. The method of any one of claims 1-56.

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