Computer numerically controlled laser cutting machine

Abstract

A method (700) includes receiving a graphical design (12) to be engraved onto a workpiece (10) by a laser engraver configured to direct a laser beam from a head (106) onto the workpiece. For each portion of the graphical design, determining an optical power level (202) for the laser beam that causes the workpiece to appear representative of the intensity value. With the head positioned to direct the laser beam at a portion of the workpiece corresponding to the portion of the graphical design, energizing a laser source (114) to direct the laser beam at the optical power level. Based on the optical power level being less than a threshold, energizing the laser source according to an enable modulation mode (402). Based on the optical power level being greater than the threshold, energizing the laser source according to an intensity modulation mode.

Description

Computer Numerically Controlled Laser Cutting MachineTECHNICAL FIELD

[0001] This disclosure relates to computer numerically controlled (CNC) machines, and more particularly to laser engraving CNC machines.BACKGROUND

[0002] Computer numerically controlled (CNC) machines are often used to add or remove material from a workpiece. In particular, laser cutting or laser engraving CNC machines direct high intensity beams of light onto a surface of the workpiece to remove or burn portions of material of the workpiece, thereby engraving an image or design onto the surface of the workpiece. Because the engraved image is formed by removing or burning the material of the workpiece, color and gradient of the engraved image is dependent on the material of the workpiece. For example, a white material that appears black when engraved may only be capable of displaying a black and white or grayscale image when engraved by the laser engraver. Traditionally, gradient or grayscale of an engraved image is achieved via a dithering pattern that alters the density of black dots or marks at the workpiece to make the engraved image appear to have lighter and darker portions.SUMMARY

[0003] One aspect of the disclosure provides a computer-implemented method that when executed on data processing hardware causes the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a workpiece by a laser engraver. The laser engraver is configured to direct a laser beam from a head of the laser engraver to engrave the graphical design onto the workpiece. For each respective portion of a plurality of portions of the graphical design, the operations include, based on an intensity value of the respective portion of the graphical design, determining an optical power level for the laser beam that causes the workpiece to appear representative of the intensity value when the laser beam is directedonto the workpiece at the determined optical power level. And for each respective portion of the plurality of portions of the graphical design, the operations include, with the head positioned relative to the workpiece to direct the laser beam at a portion of the workpiece corresponding to the respective portion of the graphical design, energizing a laser source of the laser engraver to direct the laser beam from the head at the determined optical power level. Based on the determined optical power level being less than a threshold optical power level, the operations include energizing the laser source according to an enable modulation mode. Based on the determined optical power level being greater than the threshold optical power level, the operations include energizing the laser source according to an intensity modulation mode.

[0004] Implementations of the disclosure may include one or more of the following optional features. In some implementations, energizing the laser source includes delivering an electrical current from a power source of the laser engraver to the laser source according to a duty cycle. In further implementations, an intensity signal along an intensity line to the power source adjusts an amplitude of the electrical current from the power source and an enable signal along an enable line to the power source adjusts the duty cycle of the electrical current from the power source. In even further implementations, energizing the laser source according to the enable modulation mode includes adjusting the enable signal to adjust the duty cycle of the electrical current from the power source to adjust the optical power level to the determined optical power level between a minimum optical power and the threshold optical power level. In some even further implementations, while energizing the laser source according to the enable modulation mode, the intensity signal is constant. In other even further implementations, energizing the laser source according to the intensity modulation mode includes adjusting the intensity signal to adjust the amplitude of the electrical current from the power source to adjust the optical power level to the determined optical power level between the threshold optical power level and a maximum optical power level. In some other even further implementations, while energizing the laser source according to the intensity modulation mode, the enable signal is constant.

[0005] Optionally, the maximum optical power level is based at least in part on a temperature of the laser source. The temperature at the laser source may be determined based at least in part on a temperature of cooling fluid of a cooling system of the laser engraver.

[0006] In some examples, the intensity value of the respective portion of the graphical design includes a pixel value of the respective portion of the graphical design. In some aspects, determining the optical power level for the respective portion of the graphical design includes mapping, using a table, the intensity value of the respective portion of the graphical design to the optical power level. Optionally, the laser source includes a carbon dioxide (CO2) laser tube.

[0007] Another aspect of the disclosure provides a system including data processing hardware and memory hardware in communication with the data processing hardware. The memory hardware stores instructions executed on the data processing hardware that cause the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a workpiece by a laser engraver. The laser engraver is configured to direct a laser beam from a head of the laser engraver to engrave the graphical design onto the workpiece. For each respective portion of a plurality of portions of the graphical design, the operations include, based on an intensity value of the respective portion of the graphical design, determining an optical power level for the laser beam that causes the workpiece to appear representative of the intensity value when the laser beam is directed onto the workpiece at the determined optical power level. And for each respective portion of the plurality of portions of the graphical design, the operations include, with the head positioned relative to the workpiece to direct the laser beam at a portion of the workpiece corresponding to the respective portion of the graphical design, energizing a laser source of the laser engraver to direct the laser beam from the head at the determined optical power level. Based on the determined optical power level being less than a threshold optical power level, the operations include energizing the laser source according to an enable modulation mode. Based on the determined optical power level being greater than the threshold optical power level, theoperations include energizing the laser source according to an intensity modulation mode. This aspect may include one or more of the following optional features.

[0008] Implementations of the disclosure may include one or more of the following optional features. In some implementations, energizing the laser source includes delivering an electrical current from a power source of the laser engraver to the laser source according to a duty cycle. In further implementations, an intensity signal along an intensity line to the power source adjusts an amplitude of the electrical current from the power source and an enable signal along an enable line to the power source adjusts the duty cycle of the electrical current from the power source. In even further implementations, energizing the laser source according to the enable modulation mode includes adjusting the enable signal to adjust the duty cycle of the electrical current from the power source and to adjust optical power level to the determined optical power level between a minimum optical power and the threshold optical power level. In some even further implementations, while energizing the laser source according to the enable modulation mode, the intensity signal is constant. In other even further implementations, energizing the laser source according to the intensity modulation mode includes adjusting the intensity signal to adjust the amplitude of the electrical current from the power source to adjust the optical power level to the determined optical power level between the threshold optical power level and a maximum optical power level. In some other even further implementations, while energizing the laser source according to the intensity modulation mode, the enable signal is constant.

[0009] Optionally, the maximum optical power level is based at least in part on a temperature of the laser source. The temperature at the laser source may be determined based at least in part on a temperature of cooling fluid of a cooling system of the laser engraver.

[0010] In some examples, the intensity value of the respective portion of the graphical design includes a pixel value of the respective portion of the graphical design. In some aspects, determining the optical power level for the respective portion of the graphical design includes mapping, using a table, the intensity value of the respectiveportion of the graphical design to the optical power level. Optionally, the laser source includes a carbon dioxide (CO2) laser tube.

[0011] Yet another aspect of the disclosure provides a method of estimating reproduction color for a graphical design. The computer-implemented method is executed by data processing hardware that causes the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a material by a laser engraver. Each respective portion of a plurality of portions of the graphical design includes a respective color. For each respective portion of the plurality of portions of the graphical design, the operations include estimating a reproduction color of the respective portion based on the color of the respective portion and the material. Different materials may each have unique color properties that are inherent to the specific type of material. The reproduction color is representative of the color of the respective portion when engraved onto the material. The method includes generating, using the estimated reproduction color of each portion of the plurality of portions of the graphical design, an estimated reproduction graphical design representative of the graphical design when engraved onto the material. The operations include providing the estimated reproduction graphical design for display in a graphical user interface.

[0012] Implementations of the disclosure may include one or more of the following optional features. In some implementations estimating the reproduction color of the respective portion include mapping, using a table, the color of the respective portion to the reproduction color. In some examples, estimating the reproduction color of the respective portion is further based on a respective intensity and / or respective optical power of a laser for engraving the respective portion onto the material. In some of these examples, the operations further include, for each respective portion of the plurality of portions of the graphical design, determining the respective intensity and / or the respective optical power of the laser for engraving the respective portion onto the material.

[0013] Optionally, the operations further include, after providing the estimated reproduction graphical design for display in the graphical user interface, receiving, in thegraphical user interface, a graphical design adjustment to the graphical design. For each respective portion of the plurality of portions of the graphical design, the operations may further include determining an adjusted color of the respective portion and estimating an adjusted reproduction color of the respective portion based on the determined adjusted color of the respective portion and the material. The operations may also further include generating, using the estimated adjusted reproduction color of each portion of the plurality of portions of the graphical design, an estimated adjusted reproduction graphical design representative of the adjusted graphical design when engraved onto the material. In these examples, the operations also further include providing the estimated adjusted reproduction graphical design for display in the graphical user interface. In some of these examples, the graphical design adjustment comprises at least one of a contrast adjustment or a brightness adjustment. Receiving the graphical design adjustment to the graphical design may include receiving a user input indication in the graphical user interface by a user. The user input indication may include the user interacting with a slider displayed in the graphical user interface.

[0014] In some implementations, the operations further include adjusting the color of the respective portion based on the laser engraver. In some of these implementations, the operations further include generating, using the adjusted color of each portion of the plurality of portions of the graphical design, an adjusted graphical design representative of the graphical design as supported by capabilities the laser engraver and providing the adjusted graphical for display in the graphical user interface.

[0015] An additional aspect of the disclosure provides a system for estimating reproduction color for a graphical design. The system includes data processing hardware and memory hardware in communication with the data processing hardware. The memory hardware stores instructions that when executed on the data processing hardware cause the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a material by a laser engraver. Each respective portion of a plurality of portions of the graphical design include a respective color. For each respective portion of the plurality of portions of the graphical design, the operations include estimating a reproduction color of the respective portion based on thecolor of the respective portion and the material. Different materials may each have unique color properties that are inherent to the specific type of material. The reproduction color is representative of the color of the respective portion when engraved onto the material. The method includes generating, using the estimated reproduction color of each portion of the plurality of portions of the graphical design, an estimated reproduction graphical design representative of the graphical design when engraved onto the material. The operations include providing the estimated reproduction graphical design for display in a graphical user interface.

[0016] This aspect may include one or more of the following optional features. In some implementations estimating the reproduction color of the respective portion include mapping, using a table, the determined color of the respective portion to the reproduction color. In some examples, estimating the reproduction color of the respective portion is further based on a respective intensity and / or respective optical power of a laser for engraving the respective portion onto the material. In some of these examples, the operations further include, for each respective portion of the plurality of portions of the graphical design, determining the respective intensity and / or the respective optical power of the laser for engraving the respective portion onto the material.

[0017] Optionally, the operations further include, after providing the estimated reproduction graphical design for display in the graphical user interface, receiving, in the graphical user interface, a graphical design adjustment to the graphical design. For each respective portion of the plurality of portions of the graphical design, the operations may further include determining an adjusted color of the respective portion and estimating an adjusted reproduction color of the respective portion based on the determined adjusted color of the respective portion and the material. The operations may also further include generating, using the estimated adjusted reproduction color of each portion of the plurality of portions of the graphical design, an estimated adjusted reproduction graphical design representative of the adjusted graphical design when engraved onto the material. In these examples, the operations also further include providing the estimated adjusted reproduction graphical design for display in the graphical user interface. In some of these examples, the graphical design adjustment comprises at least one of a contrast adjustmentor a brightness adjustment. Receiving the graphical design adjustment to the graphical design may include receiving a user input indication in the graphical user interface by a user. The user input indication may include the user interacting with a slider displayed in the graphical user interface.

[0018] In some implementations, the operations further include adjusting the color of the respective portion based on the laser engraver. In some of these implementations, the operations further include generating, using the adjusted color of each portion of the plurality of portions of the graphical design, an adjusted graphical design representative of the graphical design as supported by capabilities the laser engraver and providing the adjusted graphical design for display in the graphical user interface.

[0019] An additional aspect of the disclosure provides a computer-implemented method when executed on data processing hardware that causes the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a material by a laser engraver. The laser engraver is configured to direct a laser beam onto the material to engrave the graphical design onto the material. The operations also include determining a reproduction color based on a color of the graphical design. The reproduction color is representative of the color of the graphical design when engraved onto the material. Different materials may each have unique color properties that are inherent to the specific type of material. The operations include determining an optical power level for the laser beam that achieves the reproduction color of the graphical design when engraved onto the material. The operations include delivering an electrical current to a laser source of the laser engraver from a power source of the laser engraver. The electrical current energizes the laser source and causes the laser beam to be directed onto the material at the determined optical power level.

[0020] Implementations of the disclosure may include one or more of the following optional features. In some implementations, the electrical current delivered to the laser source includes an amplitude and a duty cycle. At least one of the amplitude and the duty cycle are adjusted to adjust the optical power level of the laser beam. In further implementations, an intensity signal along an intensity line to the power source adjusts the amplitude of the electrical current from the power source, and an enable signal alongan enable line to the power source adjusts the duty cycle of the electrical current from the power source. In some further implementations, based on the determined optical power level being less than a threshold optical power level, delivering the electrical current to the laser source is according to an enable modulation mode. Based on the determined optical power level being greater than the threshold optical power level, delivering the electrical current to the laser source is according to an intensity modulation mode.

[0021] In some even further implementations, while delivering the electrical current to the laser source according to the enable modulation mode, the duty cycle of the electrical current is adjusted to adjust the optical power level of the laser beam. While delivering the electrical current to the laser source according to the intensity modulation mode, the amplitude of the electrical current is adjusted to adjust the optical power level of the laser beam. In some additionally even further implementations, while delivering the electrical current to the laser source according to the intensity modulation mode, the amplitude of the electrical current is limited based on a current temperature of the laser source.

[0022] Another aspect of the disclosure provides a system including data processing hardware and memory hardware in communication with the data processing hardware. The memory hardware stores instructions executed on the data processing hardware that cause the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a material by a laser engraver. The laser engraver is configured to direct a laser beam onto the material to engrave the graphical design onto the material. The operations include determining a reproduction color based on a color of the graphical design. The reproduction color is representative of the color of the graphical design when engraved onto the material. Different materials may each have unique color properties that are inherent to the specific type of material. The operations include determining an optical power level for the laser beam that achieves the reproduction color of the graphical design when engraved onto the material. The operations include delivering an electrical current to a laser source of the laser engraver from a power source of the laser engraver. The electrical current energizes the lasersource and causes the laser beam to be directed onto the material at the determined optical power level.

[0023] Implementations of the disclosure may include one or more of the following optional features. In some implementations, the electrical current delivered to the laser source includes an amplitude and a duty cycle. At least one of the amplitude and the duty cycle are adjusted to adjust the optical power level of the laser beam. In further implementations, an intensity signal along an intensity line to the power source adjusts the amplitude of the electrical current from the power source, and an enable signal along an enable line to the power source adjusts the duty cycle of the electrical current from the power source. In some further implementations, based on the determined optical power level being less than a threshold optical power level, delivering the electrical current to the laser source is according to an enable modulation mode. Based on the determined optical power level being greater than the threshold optical power level, delivering the electrical current to the laser source is according to an intensity modulation mode.

[0024] In some even further implementations, while delivering the electrical current to the laser source according to the enable modulation mode, the duty cycle of the electrical current is adjusted to adjust the optical power level of the laser beam. While delivering the electrical current to the laser source according to the intensity modulation mode, the amplitude of the electrical current is adjusted to adjust the optical power level of the laser beam. In some additionally even further implementations, while delivering the electrical current to the laser source according to the intensity modulation mode, the amplitude of the electrical current is limited based on a current temperature of the laser source.

[0025] Yet another aspect of the disclosure provides a computer-implemented method when executed on data processing hardware causes the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a workpiece by a laser engraver. The laser engraver is configured to direct a laser beam from a head of the laser engraver to engrave the graphical design onto the workpiece. Each portion of a plurality of portions of the graphical design include a position relative to a true origin of a bed of the laser engraver. Based on movement of thehead relative to the bed to a new origin spaced from the true origin, and for each portion of the plurality of portions of the graphical design, the operations include adjusting the position relative to the true origin for the respective portion of the graphical design based on the new origin, and with the head positioned at the adjusted position, energizing a laser source of the laser engraver to direct the laser beam from the laser head onto the workpiece.

[0026] Implementations of the disclosure may include one or more of the following optional features. In some implementations, a preview laser source is operable to direct a preview laser beam from the head. An intersection of the preview laser beam with the bed corresponds to the new origin. In further implementations, the preview laser beam is concentric with the laser beam.

[0027] In some examples, adjusting the position for the respective portion of the graphical design includes centering the graphical design relative to the new origin. In other examples, adjusting the position of the respective portion of the graphical design includes adjusting a corner of the graphical design to align with the new origin. Optionally, the head is manually moved to the new origin.

[0028] An additional aspect of the disclosure provides a system including data processing hardware and memory hardware in communication with the data processing hardware. The memory hardware stores instructions executed on the data processing hardware that cause the data processing hardware to perform operations. The operations include receiving a graphical design to be engraved onto a workpiece by a laser engraver. The laser engraver is configured to direct a laser beam from a head of the laser engraver to engrave the graphical design onto the workpiece. Each portion of a plurality of portions of the graphical design include a position relative to a true origin of a bed of the laser engraver. Based on movement of the head relative to the bed to a new origin spaced from the true origin, and for each portion of the plurality of portions of the graphical design, the operations include adjusting the position relative to the true origin for the respective portion of the graphical design based on the new origin, and with the head positioned at the adjusted position, energizing a laser source of the laser engraver to direct the laser beam from the laser head onto the workpiece.

[0029] Implementations of the disclosure may include one or more of the following optional features. In some implementations, a preview laser source is operable to direct a preview laser beam from the head. An intersection of the preview laser beam with the bed corresponds to the new origin. In further implementations, the preview laser beam is concentric with the laser beam.

[0030] In some examples, adjusting the position for the respective portion of the graphical design includes centering the graphical design relative to the new origin. In other examples, adjusting the position of the respective portion of the graphical design includes adjusting a corner of the graphical design to align with the new origin. Optionally, the head is manually moved to the new origin.

[0031] The details of one or more implementations of the disclosure are set forth in the accompanying drawings and the description below. Other aspects, features, and advantages will be apparent from the description and drawings, and from the claims.DESCRIPTION OF DRAWINGS

[0032] FIG. l is a schematic view of an example laser engraving system.

[0033] FIG. 2 is a schematic view of intensity values for portions of a graphical design and optical power levels for a laser beam determined to achieve the intensity values when the laser beam is directed at a workpiece.

[0034] FIG. 3 is a comparison of a graphical design laser engraved using traditional dithering techniques and the graphical design laser engraved using adjusted optical power levels of the laser beam.

[0035] FIG. 4A shows a diagram representative of the enable signal across a range of optical power levels.

[0036] FIG. 4B shows a diagram representative of the intensity signal across the range of optical power levels.

[0037] FIG. 5 shows a diagram representative of the range of optical power levels when the laser source is energized according to the intensity modulation mode for all optical power levels of the range.

[0038] FIG. 6A shows a diagram representative of the current delivered to the laser source.

[0039] FIG. 6B shows a diagram representative of power delivered to the laser source.

[0040] FIG. 7 provides a flowchart of an exemplary arrangement of operations for a method of controlling operation of the laser engraver.

[0041] FIG. 8 is a schematic view of an example system for estimating reproduction color for a graphical design.

[0042] FIG. 9 is a schematic view of exemplary components of the system of FIG. 9, including a graphical user interface.

[0043] FIGS. 10A and 10B are schematic views of estimated color reproductions and associated mappings.

[0044] FIGS. HAand 11B are schematic views of exemplary graphical designs and estimated reproduction graphical designs.

[0045] FIG. 12 is a flowchart of an example arrangement of operations for a method for estimating reproduction color for a graphical design.

[0046] FIG. 13 is a flowchart of an exemplary arrangement of operations for a method of determining optical power levels of the laser beam of the laser engraver and controlling electrical current to generate the laser beam at the determined optical power levels.

[0047] FIG. 14 is a schematic view showing movement of the laser head relative to the bed of the laser engraver.

[0048] FIG. 15 is a flowchart of an example arrangement of operations for a method of adjusting positions of the graphical design based on user movement of the laser head.

[0049] FIG. 16 is a schematic view of an example computing device that may be used to implement the systems and methods described herein.

[0050] Like reference symbols in the various drawings indicate like elements.DETAILED DESCRIPTION

[0051] The detailed description of exemplary implementations herein makes reference to the accompanying drawings, which show exemplary implementations by way of illustration. While these exemplary implementations are described in sufficient detail to enable those skilled in the art to practice the disclosure, it should be understood that other implementations may be realized and that logical changes and adaptations in design and construction may be made in accordance with this disclosure and the teachings herein without departing from the spirit and scope of the disclosure. Thus, the detailed description herein is presented for purposes of illustration only and not of limitation.

[0052] As used herein, the terms “including,” “comprising,” “having,” and variations thereof mean “including but not limited to” unless expressly specified otherwise. Accordingly, the terms “including,” “comprising,” “having,” and variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An enumerated listing of items does not imply that any or all of the items are mutually exclusive and / or mutually inclusive, unless expressly specified otherwise.

[0053] Further, in the detailed description herein, references to “one embodiment,” “an embodiment,” “various implementations,” “one example,” “an example,” “some examples,” “one implementation,” “an implementation,” “some implementations,” etc., indicate that the embodiment, implementation, or example described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Thus, when a particular feature, structure, or characteristic is described in connection with an embodiment or an implementation, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other implementations whether or not explicitly described. Similarly, the use of the term “implementation” means an implementation having a particular feature, structure, or characteristic described inconnection with one or more implementations of the present disclosure. Absent an express correlation to indicate otherwise, an implementation may be associated with one or more implementations. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative implementations.

[0054] Laser engravers that direct a laser beam onto a workpiece to engrave an image or graphical design onto the workpiece are typically configured to engrave the graphical design using a dithering pattern. That is, the graphical design is transferred to the workpiece as a series of dots or marks engraved at a surface of the workpiece. The density or pattern of the dots relative to non-engraved portions of the surface of the workpiece causes the engraved design to appear to have shading or gradient. For example, the density of the dithering pattern may be varied across an engraved design to create a grayscale appearance for the engraved design that generally corresponds to the shading of an input graphical design. However, varying the density of engraved dots across the graphical design reduces the fidelity / resolution from the input graphical design to the engraved design.

[0055] Implementations herein are directed toward methods and systems for controlling a laser engraver to vary an optical power level of a laser beam generated by the laser engraver and directed onto the workpiece so that the resultant engraving appears representative of the shading or tones or intensity values for an input graphical design or image. That is, as the laser engraver engraves the graphical design onto the surface of the workpiece, the optical power level of the laser beam is adjusted to create variations in shading of the engraved design at the workpiece. The optical power level used to engrave respective portions of the graphical design are determined based on at least one of colors, shades, tones, intensity values, or pixel values of the input graphical design. Thus, and as described further below, the methods and systems for controlling the laser engraver produce an engraved graphical design at a workpiece with shading or gradient or grayscale without sacrificing resolution between the input image and the engraved design.

[0056] Referring to FIG. 1, a computer numerically controlled (CNC) laser engraving machine 100 (also referred to herein as a laser engraver 100) includes a bed or tray 102configured to support a workpiece 10 and a gantry system 104 configured to move a carriage or laser head 106 relative to the bed 102. For example, the carriage or laser head 106 is supported above the bed 102 by a first track or rail 108 of the gantry system 104 and the carriage or laser head 106 may be movable along a length of the first rail 108. The gantry system 104 may also include respective second tracks or rails 110 that extend along opposing sides of the bed 102 and that extend perpendicular to the length of the first rail 108. The first rail 108 may be movable along the lengths of the respective second rails 110. Thus, the gantry system 104 is configured to move the carriage or laser head 106 at least along a plane above the bed 102 and workpiece 10 via movement of the carriage or laser head 106 along the first rail 108 and movement of the first rail 108 along the second rails 110. In some examples, a height of the laser head 106 relative to the bed 102 is adjustable such that the laser head 106 is movable within a three-dimensional space relative to the bed 102 and the workpiece 10. For example, the CNC laser engraving machine 100 may include a bed lifting mechanism that is configured to controllably raise and lower the bed 102 to change the distance between the workpiece 10 supported on the bed 102 and the laser head 106.

[0057] The laser engraver 100 includes a laser source 112 that, when energized by a power source 116 associated with the laser engraver 100, generates a laser beam 114 that is directed from the laser head 106 onto the workpiece 10. For example, the laser beam 114 may be a coherent laser light with a wavelength of 10,600 nanometers. The laser source 112 may include any suitable source of electromagnetic energy. In some examples, the laser source 112 includes a carbon dioxide (CO2) laser tube or a laser diode. Further, the laser source 112 may be disposed remote from the laser head 106 and, when energized, generate the laser beam 114 that is directed from the laser head 106 via a series of mirrors or lenses or prisms between the laser source 112 and the head 106. Optionally, the laser source 112 is disposed at the laser head 106 and operable to direct the laser beam 114 directly from the laser source 112 at the head 106 onto the workpiece 10.

[0058] A control module 118 of the laser engraver 100 includes data processing hardware 120 and memory hardware 122 in communication with the data processinghardware 120. The memory hardware 122 stores instructions that, when executed on the data processing hardware 120, cause the data processing hardware 120 to perform operations. For example, the memory hardware 122 stores instructions for controlling operation of the laser engraver 100 to engrave a graphical design or image 12 onto the workpiece 10. In some examples, and as discussed further below, the graphical design 12 is received from a design generating program operated at a user device 14 that is in communication with the control module 118 of the laser engraver 100.

[0059] As shown in FIG. 2, the graphical design 12 received from the user device 14 may be segmented / delineated into a plurality of portions 16, 16a-n. For example, each portion 16 of the plurality of portions 16 of the graphical design 12 may represent a pixel of a digital image representative of the graphical design 12. Accordingly, each portion 16 of the graphical design 12 may include an intensity value or pixel value 18, 18a-n that expresses the color or shade or tone of the particular portion 16 of the graphical design 12, and a corresponding position 20, 20a-n of the portion 16 at the workpiece 10. Thus, when the laser engraver 100 is operated to transfer the graphical design 12 onto the workpiece 10, the laser beam 114 is directed onto the workpiece 10 at each position 20 corresponding to portions 16 of the graphical design 12 and engraves the position 20 of the workpiece 10 to appear representative of the intensity value 18 of the respective portion 16.

[0060] To achieve appearance of different intensity values 18 for respective portions 16 of the engraved graphical design 12, an optical power level 202 of the laser beam 114 is adjusted according to the intensity value 18 while engraving the particular portion 16 of the graphical design 12 at the workpiece 10. The resultant engraving thus includes differing shades or tones or gradient at respective portions 16 of the graphical design 12 that correspond to intensity values 18 of the graphical design 12 received from the user device 14. This is in contrast to traditional laser engravers, which maintain a stable power level of the laser beam and adjust the density of the dithering pattern for respective portions of the design to convey the impression of different intensity values of the design. As shown in FIG. 3, by adjusting the optical power level 202 of the laser beam 114 to achieve appearance of different intensity values 18, the laser engraver 100 increases theresolution of each portion 16 of the engraved graphical design 12 at the respective portions 20 of the workpiece 10 compared to traditional systems, and thus achieves a more true grayscale representative of the contrast and colors depicted in the graphical design 12..

[0061] Thus, and with continued reference to FIG. 2, for each portion 16 of the plurality of portions 16 of the graphical design 12, the control module 118 determines an optical power level 202, 202a-n for the laser beam 114 that causes the workpiece 10 to appear representative of the respective intensity value 18 when the laser beam 114 is directed onto the workpiece 10 at the determined optical power level 202. For example, the optical power levels 202 correspond to respective strength or power settings of the laser beam 114, where the amount of electrical current through the laser source 112 is adjusted to alter the output of the laser beam 114. The optical power level 202 for the laser beam 114 may be limited by operational parameters of the laser source 112. For example, a laser source 112 configured to receive up to 22 milliamps of current may generate up to about 50 Watts of optical power.

[0062] In the illustrated example, a first portion 16a of the graphical design 12 has a first intensity value 18a and thus the laser beam 114 is adjusted to a first optical power level 202a (e.g., 25 percent of the maximum output of the laser source 112) when directed at the corresponding first portion 20a of the workpiece 10. A second portion 16b of the graphical design 12 has a second intensity value 18b greater than the first intensity value 18a and thus the laser beam 114 is adjusted to a second optical power level 202b greater than the first optical power level 202a (e.g., 50 percent of the maximum output of the laser source 114) when directed at the corresponding second portion 20b of the workpiece 10. The optical power level 202 may be adjustable up to the maximum output of the laser source 114 to achieve maximum intensity values 18. Thus, because the optical power level 202 of the laser beam 114 is adjusted when directed at different portions 20 of the workpiece 10, the respective portions 16 of the engraved graphic design 12 will appear representative of the different intensity values 18 at the workpiece 10.

[0063] Referring to FIGS. 1 and 2, the optical output levels 202 corresponding to the respective intensity values 18 may be listed in a table 204 stored in memory hardware 122 of the control module 118. Thus, when the control module 118 determines the optical power level 202 for respective portions 16 of the graphical design 12, the control module 118 maps the intensity values 18 of the respective portions 16 to corresponding optical power levels 202 listed in the table 204. The optical power level 202 may be output from the table 204 as a percentage or portion of the maximum output of the laser source 112, as an analog power level in Watts, or as a target electrical current delivered from the power source 116 to the laser source 112.

[0064] In other words, based on the graphical design 12, the control module 118 controls operation of the laser engraver 100 to engrave the graphical design 12 onto the workpiece 10. For example, the control module 118 controls operation of the gantry system 104 to adjust a position of the laser head 106 relative to the workpiece 10 so that the laser beam 114 directed from the laser head 106 engraves the respective portions 16 of the graphical design 12 at the corresponding positions 20 of the workpiece 10. With the head 106 positioned relative to the workpiece 10 to direct the laser beam 114 at the corresponding position 20 of the workpiece 10, the control module 118 energizes the laser source 112 to direct the laser beam 114 from the head 106 at the optical power level 202 for the respective portion 16 of the graphical design 12.

[0065] According to various implementations, the control module 118 energizes the laser source 112 to generate the laser beam 114 at respective optical power levels 202 by controlling a high voltage electrical current 124 from the power source 116 to the laser source 112 by adjusting a duty cycle 126 and / or an amplitude 128 of the electric current 124 to achieve the optical power level 202. The electrical current 124 generates a load at the laser source 112 to generate the laser beam 114 at the desired optical power level 202. An intensity signal 130 along an intensity line 132 to the power source 116 adjusts the amplitude 128 of the electrical current 124 from the power source 116 and an enable signal 134 along an enable line 136 to the power source 116 adjusts the duty cycle 126 of the electrical current 124 from the power source 116. A duty cycle 126 of 65 percentmay correspond to the maximum intensity value 18 and maximum optical power level 202 in the table 204.

[0066] Referring to FIGS. 4A and 4B, the control module 118 energizes the laser source 112 according to an enable modulation mode 402 and / or an intensity modulation mode 404 based on the optical power level 202 of the laser beam 114 to be delivered from the laser head 106. While energizing the laser source 112 according to the enable modulation mode 402, a duty cycle 406 of the enable signal 134 (denoted along the y- axis of FIG. 4A as ‘Enable Line Duty Cycle (%)’) is adjusted to adjust the duty cycle 126 of the electrical current 124 and thus the optical power level 202 of the laser beam 114, and a duty cycle 408 of the intensity signal 130 (denoted along the y-axis of FIG. 4B as ‘Intensity Line Duty Cycle (%)’) is kept constant (such as at a 50 percent duty cycle). While energizing the laser source 112 according to the intensity modulation mode 404, the duty cycle 408 of the intensity signal 130 is adjusted to adjust the electrical current 124 and thus the optical power 202 of the laser beam 114 and the duty cycle 406 of the enable signal 134 may be kept constant at 100 percent.

[0067] FIG. 4A shows a diagram 400a of the duty cycle 406 of the enable signal 134 across a range of duty cycles 126 of the electrical current 124 corresponding to optical power levels 202 of the laser beam 114. Similarly, FIG. 4B shows a diagram 400b of the duty cycle 408 of the intensity signal 130 across the range of duty cycles 126 of the electrical current 124 corresponding to optical power levels 202 of the laser beam 114. As shown, the control module 118 switches between the enable modulation mode 402 and the intensity modulation mode 404 at a threshold duty cycle 126T corresponding to a threshold optical power level 202T. That is, based on the optical power level 202 of the laser beam 114 being less than the threshold optical power level 202T, the laser source 112 is energized according to the enable modulation mode 402 and, based on the optical power level 202 of the laser beam 114 being greater than the threshold optical power level 202T, the laser source 112 is energized according to the intensity modulation mode 404.

[0068] In some examples, the control module 118 energizes the laser source 112 according to a hybrid modulation mode, where the enable signal 134 and the intensitysignal 130 may both be adjusted to adjust the duty cycle 126 and / or amplitude 128 of the electrical current 124 and thus the optical power level 202 of the laser beam 114. In other words, one of the enable signal 134 or the intensity signal 130 does not need to be kept constant while the other is varied. Rather, and as discussed in further detail below, the control module 118 may adjust the intensity signal 130 to adjust the amplitude 128 of the electrical current 124 and the control module 118 may adjust the enable signal 134 to adjust the duty cycle 126 of the electrical current 124. For example, these adjustments may be performed concurrently. In various implementations, the optical power level 202 of the laser beam 114 may be exclusively or at least primarily adjusted via intensity signal modulation within a first operating regime, the optical power level 202 of the laser beam 114 may be exclusively or at least primarily adjusted via enable signal modulation within a second operating regime, and / or the optical power level 202 of the laser beam 114 may adjusted via both intensity signal modulation and enable signal modification within a third operating regime. In various embodiments, the control module 118 may be configured to promote linearity and / or continuity in the resulting optical power level 202. Said differently, the control module 118 may be configured to control operation of the laser head such that a graph / plot of the produced optical power level as a function of the requested optical power level is substantially linear and / or substantially continuous at least across certain operating ranges / regimes. That is, the control module 118 may be configured to operate in the enable modulation mode, the intensity modulation mode, and / or the hybrid modulation mode in order to promote linearity and / or continuity of the optical output / response across a range of requested inputs. Additional details are included below with reference to FIGS. 5, 6A, and 6B regarding this linearity.

[0069] FIG. 5 shows a diagram 500 including lines 502a-c representative of optical power levels 202 (y-axis) of the laser beam 114 when the laser source 112 is energized according to the intensity modulation mode 404 across all optical power levels 202. That is, the duty cycle 406 of the enable signal 134 is at 100 percent and the duty cycle 408 (x- axis) of the intensity signal 130 is adjusted to adjust the electrical current 124 and thus the optical power level 202 of the laser beam 114. The first line 502a represents optical power levels 202 of the laser beam 114 when energized by a power source 116 delivering108 Volts, the second line 502b represents optical power levels 202 of the laser beam 114 when energized by a power source 116 delivering 120 Volts, and the third line 502c represents optical power levels 202 of the laser beam 114 when energized by a power source 116 delivering 126 Volts.

[0070] As shown in FIG. 5, when the duty cycle 408 of the intensity signal 130 is at lower values (e.g., between 0 percent and 30 percent), the optical power level 202 of the laser beam 114 increases dramatically in response to small increases in the duty cycle 408 as compared to when the duty cycle 408 of the intensity signal 130 is at higher values (e.g., above 30 percent or above 40 percent or above 50 percent). Control of the optical power level 202 of the laser beam 114 is generally linear when the duty cycle 408 of the intensity signal 130 is at the higher values. Thus, energizing the laser source 112 according to the intensity modulation mode 404 across all optical power levels 202 provides a nondinear and / or a discontinuous curve of optical power levels 202 that makes it difficult to achieve lower power levels 202 that may be necessary to achieve lower intensities 18 of the engraved graphical design 12.

[0071] Because the enable modulation mode 402 provides more linear control of the lower range of optical power levels 202 at lower duty cycles 126 (such as between 0 percent and 50 percent duty cycles) (e.g., FIG. 6A), the threshold optical power level 202T is set so that the laser source 112 may be energized according to the enable modulation mode 402 when adjusting the optical power level 202 between a minimum optical power level 202 (such as corresponding to a 0 percent duty cycle 126) and the threshold optical power level 202T. The laser source 112 may be energized according to the intensity modulation mode 404 when adjusting the optical power level 202 between the threshold optical power level 202T and a maximum optical power level 202 (such as corresponding to a 65 percent duty cycle 126). Further, because the optical power levels 202 at the lower levels of the duty cycle 408 of the intensity signal 130 vary based on the voltage of the power source 116, the threshold optical power level 202T may be set or adjusted based on the voltage of the power source 116. Here, the threshold optical power level 202T is calibrated based on a power source 116 delivering 120 Volts and is set at a 50 percent duty cycle 126.

[0072] FIG. 6A shows a diagram 600a representative of the current 124 (y-axis) delivered to the laser source 112 by the power source 116 at the range of duty cycles 126 (x-axis) that correspond to the optical power levels 202 for different frequencies of the enable signal 134. FIG. 6B shows a diagram 600b representative of the power or amplitude 128 of the electrical current 124 (y-axis) of the laser beam 114 at the range of duty cycles 126 (x-axis) that correspond to the optical power levels 202 for different frequencies of the enable signal 134. As shown, the laser source 112 is energized according to the enable modulation mode 402 when the current 124 is below 18 milliamps and the laser source 112 is energized according to the intensity modulation mode 404 when the current is above 18 milliamps, where 18 milliamps is delivered to the laser source 112 to produce the threshold optical power level 202T at the threshold duty cycle 126T of 50-percent (50%). Individual pulses of the enable modulation mode 402 may be best disguised with a frequency of the enable signal 134 at two (2) kilohertz. Thus, delivering current 124 to the laser source 112 with an enable signal 134 frequency at two (2) kilohertz under enable modulation mode 402 between zero (0) milliamps and 18 milliamps and under intensity modulation mode 404 between 18 milliamps and 22 milliamps provides generally smooth (continuous) and linear control of the optical power level 202 of the laser beam 114.

[0073] FIG. 7 provides a flowchart of an exemplary arrangement of operations for a method 700 of controlling operation of the laser engraver 100. The operations may execute on the data processing hardware 120 of the control module 118 based on executable instructions stored on the memory hardware 122 of the control module 118 of FIG. 1. At operation 702, the method 700 includes receiving a graphical design 12 to be engraved onto a workpiece 10 by the laser engraver 100. The laser engraver 100 is configured to direct a laser beam 114 from a head 106 of the laser engraver 100 to engrave the graphical design 12 onto the workpiece 10. The method 700 includes, at operation 704, for each respective portion 16 of a plurality of portions 16 of the graphical design 12, and based on an intensity value 18 of the respective portion 16 of the graphical design 12, determining an optical power level 202 for the laser beam 114 that causes the workpiece 10 to appear representative of the intensity value 18 when the laser beam 114is directed onto the workpiece 10 at the determined optical power level 202. And, for each respective portion 16 of the plurality of portions 16 of the graphical design 12, the method 700 includes at operation 706, with the head 106 positioned relative to the workpiece 10 to direct the laser beam 114 at a portion 20 of the workpiece 10 corresponding to the respective portion 16 of the graphical design 12, energizing a laser source 112 of the laser engraver 100 to direct the laser beam 114 from the head 106 at the determined optical power level 202. At operation 706, the method 700 includes, based on the determined optical power level 202 being less than a threshold optical power level 202T, energizing the laser source 112 according to an enable modulation mode 402. At operation 708, the method 700 includes, based on the determined optical power level 202 being greater than the threshold optical power level 202T, energizing the laser source 112 according to an intensity modulation mode 404.

[0074] Referring back to FIG. 1, in some implementations, the duty cycle 126 of the electrical current 124 energizing the laser source 112 during the intensity modulation mode 404 is calibrated based on a temperature 138 at the laser source 112 to avoid overheating and damaging the laser source 112. For example, the laser source 112 may be configured to receive up to 22 milliamps of electrical current 124 and the power supply 116 may provide up to 26 milliamps of electrical current 124. The power usage of the laser source 112 is dependent upon the temperature 138 at the laser source 112.

[0075] Typically, the cooling system 140 (e.g., a water cooling system) may operate to maintain the laser source 112 at or below a constant temperature 138 known to be a safe operating temperature for the laser source 112. However, high ambient temperatures at the laser engraver 100 may prevent or preclude the cooling system 140 from maintaining the constant operating temperature 138.

[0076] Thus, the control module 118 adjusts the power to the laser source 112 based on the detected temperature 138 at the laser source 112. In other words, the current 124 to the laser source 112 may be limited to maintain a safe operating temperature at the laser source 112. For example, a maximum duty cycle 126 of the current 124 corresponding to a maximum optical power 202 may be determined based on the detected temperature 138, where the maximum duty cycle 126 is determined based on maintainingthe temperature 138 at the laser source 1 12 at or below a safe operating temperature threshold. Thus, a maximum optical power level 202 is based at least in part on the temperature 138 at the laser source 112. The temperature 138 at the laser source 112 may be determined based on a temperature of a cooling fluid from a cooling system 140 of the laser engraver 100.

[0077] Thus, when the temperature 138 at the laser source 112 is below the safe operating temperature threshold, the control module 118 may allow for rapid increases in the duty cycle 126 to achieve desired optical power levels 202. When the temperature 138 is at or near the safe operating temperature threshold, the control module 118 may prevent increases in the duty cycle 126 or only allow for gradual increases in the duty cycle 126 toward achieving the desired optical power level 202.

[0078] FIGS. 8-12 are directed toward techniques for estimating reproduction color for the graphical design 12. These techniques are generally configured to analyze a graphical design to estimate a color reproduction of the graphical design 12 on a physical medium or material of the workpiece 10. Based on the estimated color reproduction, a display 816 (e.g., of a user device) may be configured to visually display the estimate to a user. For example, a user 80 may provide a sample image or graphical design (e.g., via a user interface 910) to a design generating program 900. The design generating program 900 may estimate the color reproduction of the graphical design 12 on another medium and, via the user interface 910, display a visual representation of the estimated color reproduction to the user 80 for easy comparison with the original graphical design 12.

[0079] In some examples, the user interface 910 allows the user 80 to adjust one or more parameters of the sample graphical design (e.g., brightness, contrast, etc.). In response to the user adjusting the one or more parameters, the design generating program 900 may update the estimated color reproduction and update the visual representation of the estimated color reproduction to give the user real-time feedback on the effects of adjusting the one or more parameters of the graphical design.

[0080] FIG. 8 provides a system 800 having an example design preparation environment (also referred to as environment) that includes the user 80 using the user device 14 (also referred to as the user device 14) to upload or create or edit or otherwiseinteract with the graphical design 12 (also referred to as a unique design 12, a unique graphical design 12, or a design 12, or the graphical design 12). The user device 14 may include data processing hardware 812 and memory hardware 814 in communication with the data processing hardware 812. The memory hardware 814 may store instructions thereon that when executed on the data processing hardware 812, causes the data processing hardware 812 to execute a design generating program 900 (also referred to as designer 900) for uploading, creating, and / or editing the graphical design 12 during the design process. As described in greater detail below, the design generating program 900 may be executed by processing / memory hardware of the user device 14 and / or by data processing hardware of a post-design processing machine 830 (e.g., laser engraver 100) and / or by a remote computing entity 840 (e.g., a server) having data processing hardware 842 and memory hardware 844. Notably, some or all of the functionality performed by the user device 14 may be performed on the post-design processing machine 830 instead of, or in addition to, the user device 14.

[0081] The design generating program 900 obtains or receives (e.g., from the user 80) the graphical design 12. For example, the user 80 may select the graphical design 12 from a content library associated with the design generating program 900 (e.g., the design generating program 900 may retrieve the graphical design from a remote data store 825), the user 80 may upload or otherwise provide the design generating program 900 access to the graphical design 12, and / or the user 80 may design / create the graphical design 12 within the design generating program 900. In some examples, the graphical design is an image, such as from a JPEG image file, a PNG image file, a TIFF image file, etc. The designer 900 may communicate the design 12 to the post-design processing machine 830 for post-design processing operations that may include an engraving, burning, printing, and / or a converting process to implement the graphical design 12 on a material 832 (the material 832 may be referred to as the workpiece 10). For example, the post-design processing machine 830 includes the laser engraver 100 that uses the laser beam 114 to engrave and / or burn and / or etch the graphical design 12 into a material 832 (e.g., wood, metal, leather, etc.). That is, the post-design processing machine 830 may convert the graphical design 12 into a physical product or other tangible medium.

[0082] In the example shown in FIG. 8, the designer 900 communicates the graphical design 12 to a post-design processing machine 830 configured to implement the received graphical design 12 on a material 832. The designer 900 may communicate the graphical design 12 to the post-design processing machine 830 via an indirect connection (e.g., a network 820) or a direct connection (e g., using a wired or wireless connection as shown by the dotted line of FIG. 8). In the example shown, the post-design processing machine 830 includes the laser engraver 100 configured to engrave the graphical design 12 onto a material 832. The post-design processing machine 830 may be capable of performing, without limitation, one or more of the following actions on a material 832: etching, burning, engraving, embossing, stitching, heat-pressing, printing, drawing, or three- dimensional printing. The post-design processing machine 830 may include a waterjet tool in some scenarios.

[0083] The user device 14 may correspond to any computing device associated with the user 80 and capable of executing the design generating program 900 (i.e., the designer 900) to generate the graphical design 12. Some examples of user devices 14 include, but are not limited to, mobile phones, tablets, laptops, desktop computers, etc. In some examples, the design generating program 900 executes on the post-design processing machine 830 or a remote server 840. Here, the designer 900 may refer to a software application hosted on the user device 14 or some portion of a software application hosted on the user device 14. For instance, the designer 900 may include a module within larger graphics editor software. Additionally or alternatively, the designer 900 may be a proprietary application or a portion of a proprietary application. For instance, the designer 900 may include a proprietary application specific to the post-design processing machine 830. Optionally, the designer 900 runs at least partially on the post-design processing machine 830 and / or the remote server 840.

[0084] In some implementations, the designer 900 is configured to display, on a screen / di splay 816 in communication with the data processing hardware 812, a graphical user interface 910 that enables the user 80 to interact with the designer 900 to perform design functions. Here, the user 80 may interact with the graphical user interface 910 onthe screen 816 of the device 14 as the data processing hardware 812 of the device 14 executes the designer 900.

[0085] In some examples, the graphical design 12 includes the plurality of portions 16, 16a-n and / or the designer 900 may determine the plurality of portions 16 of the graphical design 12. For example, the designer 900 may divide the graphical design 12 into the plurality of portions 16. Each portion 16 may be the same size. In some examples, each portion 16 represents a pixel or a group of pixels of the graphical design 12. In other examples, the graphical design 12 is divided into a fixed number of portions 16 and the size of each portion 16 is dependent upon the size of the graphical design 12. The designer 900 may determine, for each respective portion 16 of the graphical design 12, a respective color 906, 906a-n of the respective portion 16. The determined color 906 is, for example, an average, a weighted average, or a median of all of the colors of the respective portion 16. When the portion 16 represents a single pixel of the graphical design 12, the determined color 906 may be the color that most closely represents the color of the pixel and when the portion 16 represents multiple pixels, the determined color 906 may be any color that represents some or all of the pixels. The color 906 may be referred to as the intensity value 18.

[0086] The designer 900, in some implementations, estimates a reproduction color 1006, 1006a-n for each portion 16 based on the determined color 906 of the respective portion 16 and the material 832 selected for or associated with the graphical design 12. The reproduction color 1006 is representative of the determined color 906 of the respective portion when engraved onto the material 832. Different materials may each have unique color properties that are inherent to the specific type of material. That is, the post-design processing machine 830, in some implementations, is not capable of exactly reproducing each color of the graphical design 12 onto the material 832 due to the inherent color properties of the specific type of material 832 the user has selected to implement the graphical design 12. For example, the post-design processing machine 830 is capable of producing various levels of blacks, grays, and whites, but not other colors (e.g., grayscale). In some implementations, the post-design processing machine 830 varies an intensity of a laser beam 114 to produce different colors on the material832. By the same notion, varying the magnitude of intensity of the laser beam 1 14, in turn causes a magnitude of optical power 202 of the laser beam 114 to change. As such, changing the optical power level 202 of the laser 114 causes different colors to be produced on the material 832. For example, a lower intensity laser beam 114, and thus lower optical power 202, may produce a lighter color (e.g., a gray) in a certain type of material while a higher intensity laser beam 114, and thus higher optical power 202, may produce a darker color (e.g., a black) in the certain type of material. Moreover, the type of the material 832 may affect the appearance of the graphical design 12 produced by the post-design processing machine 830. For example, a particular laser intensity (and corresponding optical power 202) may produce a first color on a first type of material while the same particular laser intensity and optical power 202 may produce a different second color on a second type of material that is different than the first type of material. Accordingly, the reproduction color 1006 may represent a color that the post-design processing machine 830 can produce on the material 832 that most closely matches the determined color 906 for each respective portion 16 of the graphical design.

[0087] Referring now to FIG. 9, in some examples, the designer 900 generates, using the estimated reproduction color 1006 of each portion 16, an estimated reproduction graphical design 1102 representative of the graphical design 12 when engraved onto the material 832. The estimated reproduction graphical design 1102 may correspond to a graphical simulation that simulates the appearance of the graphical design 12 when engraved onto the particular material 832. The graphical user interface 910, in some implementations, has windows 912, 912a-c including a graphical design window 912a that the user 80 may interact with via touch, stylus, mouse / cursor, gesture, and / or speech. The graphical design window 912a may be configured to display the graphical design 12. In some examples, the graphical design window 912a displays the graphical design 12 as provided / created by the user 80 (e.g., the same or essentially the same image parameters for an image, such as brightness, contrast, etc.). In other examples, the designer 900, prior to displaying the graphical design 12, adjusts the color 906 of one or more portions 16 of the graphical design 12 based on the capabilities of the post-design processing machine 830.

[0088] In some implementations, the graphical user interface 910 includes a reproduction graphical design window 912, 912b configured to display the estimated reproduction graphical design 1102. The graphical design window 912a and the reproduction graphical design window 912b may be situated within the graphical user interface 910 such that the user 80 may easily visually compare the graphical design 12 with the estimated reproduction graphical design 1102. That is, the color differences between the graphical design 12 and the estimated reproduction graphical design 1102 are readily apparent to allow the user 80 to ascertain a quality or other metric of the estimated reproduction graphical design 1102 which represents an estimate of how the graphical design 12 will appear once engraved on the material 832.

[0089] FIG. 9 also illustrates that the graphical user interface 910 may include additional windows 912 that allow the user 80 to add or to modify / manipulate content displayed in the graphical design window 912a and / or the reproduction graphical design window 912b or to perform various commands related to the design generating program (i.e., the designer) 900. One or more of the windows 912 may contain selectable icons 914, 914a-c that the user 80 may select to facilitate the creation or the modification of a design 12. Each icon 914 may correspond to a particular function depending on the window 912 where the particular icon 914 is located in the graphical user interface 910. For instance, the graphical user interface 910 may include a command window 912c providing various commands that govern functions of the designer, such as an accept command to ensure that a user 80 wants to perform a particular action or function selected. Here, the user 80 may select a “done” icon 914c in the command window 912c to provide the accept command. The command window 912c may further include cancel and edit icons 914a, 914b that permit the user to cancel a particular selection and edit a graphical design 12. By having command icons 914, the user interface 910 may navigate between windows 912 or know when functionality related to a particular window 912 is complete.

[0090] Referring now to FIG. 10A, in some implementations, the designer 900 estimates the reproduction color 1006 using a table 1002, such as a lookup table. The table 1002 may be stored on at least one of the user device 14, the data storage 825, or atany other memory hardware in communication with the designer 900 (e.g., at the postdesign processing machine 830). The table 1002 includes a representation of each of the reproduction colors 1006. Each reproduction color 1006 may be associated with respective color metadata 1008, 1008a-n defining the reproduction color 1006 and / or providing mapping information to respective colors 906. For example, the metadata 1008 includes a list of the materials and / or laser intensities and / or optical powers 202 that cause the respective reproduction color 1006. That is, the color metadata 1008 indicates the laser intensities (and / or optical powers 202) and / or the materials 832 that, when engraved by the post-design processing machine 830, result in the respective reproduction color 1006. In some implementations, the color metadata 1008 includes the colors 906 the reproduction color 1006 maps to or from.

[0091] Referring now to FIG. 10B, in some implementations, the designer 900, estimates the reproduction color 1006 by mapping, using the table 1002, the determined color 906 of each portion 16 to the appropriate reproduction color 1006 (e.g., the closest matching reproduction color 1006). The designer may use the color metadata 1008 to provide the mapping. For example, the color metadata 1008 indicates a range of colors 906 that map to each respective reproduction color 1006. In some examples, the mapping depends on the material 832 and / or a determined optical power 202 for the respective portion 16. In other examples, the mapping dictates the laser intensity / optical power 202 appropriate for the appropriate reproduction color 1006 and the material 832. For example, the designer 900 determines the reproduction color 1006 that most closely matches the color 906 (via any known color matching methods, such as by determining a distance between the color space of the color 906 and each reproduction color 1006) and, based on the color metadata 1008 for the selected reproduction color 1006, determines the appropriate laser intensity for the given material 832.

[0092] In some examples, the designer 900 determines the reproduction color 1006 most similar to the color 906 of the corresponding portion 16 of the material 832 and selects the determined reproduction color 1006 for the estimated reproduction graphical design 1102. In other examples, the designer 900 determines that the color 906 is within a range established by two different reproduction colors 1006 from the table 1002 (i.e.,the color 906 lies “between” the two reproduction colors 1006) and the designer 900 interpolates a new reproduction color 1006 based on the two reproduction colors 1006. For example, the designer 900 determines a first laser intensity (and / or first optical power 202) required for the first reproduction color 1006 and a second laser intensity (and / or second optical power 202) required for the second reproduction color 1006, then the designer 900 determines a third laser intensity (and / or third optical power 202) between the first laser intensity and the second intensity that results in the new reproduction color 1006 that more closely matches the color 906 than the first or second reproduction colors 1006.

[0093] Referring now to FIG. 11A, a schematic view 1100A includes an exemplary graphical user interface 910 with the graphical design window 912a and the reproduction graphical design window 912b. Here, the graphical design window 912a displays the graphical design 12 which, in this example, is an image. The reproduction graphical design window 912b displays the estimated reproduction graphical design 1102 representative of appearance of the graphical design 12 once engraved on the material 832 (e.g., based on the table 1002 of FIGS. 10A and 10B). In some scenarios, the estimated reproduction graphical design 1102 makes apparent one or more deficiencies in engraving the graphical design 12 onto the material 832. For example, the graphical design 12 may appear washed out or otherwise render important details difficult to discern.

[0094] Referring now to FIG. 1 IB, in some examples, the designer 900 receives a graphical design adjustment (e.g., a contrast adjustment and / or a brightness adjustment) to the graphical design 12 (e.g., from a user interaction from the user 80 with the graphical user interface 910) indicating an adjusted graphical design 12, 12A. For each respective portion 16 of the adjusted graphical design 12, the designer 900 determines an adjusted color 906 for the respective portion and the corresponding adjusted reproduction color 1006 for the respective portion 16. Based on the adjusted reproduction colors 1006, the designer 900 generates an estimated adjusted reproduction graphical design 1102, 1102A. The designer 900 may transmit the estimated adjusted reproduction graphical design 1102A to the graphical user interface 910 for display to the user 80.

[0095] That is, the designer 900, in some examples, allows the user 80 to edit or adjust the graphical design 12 to generate corresponding changes to the estimated reproduction graphical design 1102. Here, a schematic view 1100B includes the graphical user interface 910 of FIG. 11 A with additional user inputs 1110, 11 lOa-c to allow user 80 to interact with the graphical user interface 910 (e.g., via one or more user interactions). In this example, the user inputs 1110 include a contrast slider 1110a and a brightness slider 1110b. Optionally, the user inputs 1110 may additionally or alternatively include an auto button 1110c that automatically adjusts features of the image for image enhancement. The user 80 may interact with the user inputs 1110 to provide the graphical design adjustments to the designer 900. In response, the designer 900 adjusts or updates the estimated reproduction graphical design 1102 to provide the user 80 with real-time feedback on the effects of the graphical design adjustments. This feedback allows the user 80 to determine when the resulting estimated reproduction graphical design 1102 meets an acceptable quality threshold. Once the user 80 is satisfied, the user 80 may instruct the designer 900 to submit the graphical design 12 to the post-design processing machine 830 for production of the graphical design 12 using the material 832. While the examples herein discuss sliders 11 lOa-b for contrast and brightness controls, the designer 900 may implement any number of user inputs 1110 (e.g., radio buttons, text fields, drop down lists, voice inputs, etc.) to allow adjustment of any number of graphical design parameters.

[0096] FIG. 12 is a flowchart of an exemplary arrangement of operations for a method 1200 of estimating reproduction color for a graphical design. The method 1200, at operation 1202, includes receiving a graphical design 12 to be engraved onto a material 832 by a laser engraver 830. Each respective portion 16 of a plurality of portions 16 of the graphical design 12 includes a respective color 906. The graphical design 12 may be received at the design generating program 900 (e.g., a graphical user interface 910 of the design generating program 900 provides the graphical design 12 to a different module or function of the design generating program 900) or at a different application executing locally or remotely to the design generating program 900 (e.g., at a remote server 840 or the laser engraver 830). The design generating program 900 may be executing at a userdevice 14, at a laser engraver 830, at a remote server 840, or at any combination of the three. For example, a portion of the design generating program 900 executes at a user device 14 while a different portion of the design generating program 900 executes at a laser engraver in communication with the user device 14. At operation 1204, the method 1200 includes, for each respective portion 16 of the plurality of portions 16 of the graphical design 12, estimating a reproduction color 1006 of the respective portion 16 based on the color 906 of the respective portion 16 and the material 832. As aforementioned, different materials may each have unique color properties that are inherent to the specific type of material. That is, the laser engraver 830 may not be capable of exactly reproducing each color of the graphical design 12 onto the material 832 due to the inherent color properties of the specific type of material 832 selected by the user. The reproduction color 1006 is representative of the color 906 of the respective portion 16 when engraved onto the material 832. The method 1200, at operation 1206, includes generating, using the estimated reproduction color 1006 of each portion 16 of the plurality of portions 16 of the graphical design 12, an estimated reproduction graphical design 1102 representative of the graphical design 12 when engraved onto the material 832. At operation 1208, the method 1200 includes providing the estimated reproduction graphical design 1102 for display in a graphical user interface 910.

[0097] FIG. 13 is a flowchart of an exemplary arrangement of operations for a method 1300 of determining optical power levels 202 of the laser beam 114 to be generated by the laser source 112 based on a desired output reproduction color 1006 at the material 832 of the workpiece 10 and controlling electrical current 124 from the power source 116 to generate the laser beam 114 at the determined optical power levels 202. At operation 1302, the method 1300 includes receiving a graphical design 12 to be engraved onto a material 832 by a laser engraver 830, such as the laser engraver 100. The laser engraver 100, 830 is configured to direct a laser beam 114 onto the material 832 to engrave the graphical design 12 onto the material 832. At operation 1304, the method 1300 includes determining a reproduction color 1006 based on a color 906 of the graphical design 12. For example, the graphical design 12 may be received from a design generating program 900 executing on a user device 14, where the color 906 of one ormore portions 16 of the graphical design 12 are selected by the user 80 at the user device 14. Optionally, the color 906 of one or more portions 16 of the graphical design 12 are inherent to the graphical design 12. The reproduction color 1006 is representative of the color 906 of the graphical design 12 when the graphical design 12 is engraved onto the material 832. For example, the reproduction color 1006 may be a grayscale transformation of the color 906 to represent the color 906 when engraved onto the material 832.

[0098] At operation 1306, the method 1300 includes determining an optical power level 202 for the laser beam 114 that achieves the reproduction color 1006 of the graphical design 12 when engraved onto the material 832. For example, determining the optical power level 202 corresponding to the reproduction color 1006 may include mapping, using a table 204, the reproduction color 1006 and / or the color 906 of the graphical design 12 to the optical power level 202. At operation 1308, the method 1300 includes delivering an electrical current 124 to a laser source 112 of the laser engraver 100, 830 from a power source 116 of the laser engraver 100, 830. The electrical current 124 energizes the laser source 112 and causes the resultant laser beam 114 to be directed onto the material 832 at the determined optical power level 202.

[0099] The electrical current 124 delivered to the laser source 112 includes an amplitude 128 and a duty cycle 126. At least one of the amplitude 128 and the duty cycle 126 of the electrical current 124 are adjusted to adjust the optical power level 202 of the laser beam 114. For example, an intensity signal 130 along an intensity line 132 to the power source 116 adjusts the amplitude 128 of the electrical current 124 and an enable signal 134 along an enable line 136 to the power source 116 adjusts the duty cycle 126 of the electrical current 124.

[0100] In some examples, the electrical current 124 is delivered to the laser source 112 according to an enable modulation mode 402, such as when the determined optical power level 202 is less than a threshold optical power level 202T. While delivering the electrical current 124 to the laser source 112 according to the enable modulation mode 402, the duty cycle 126 of the electrical current 124 is adjusted to adjust the optical power level 202 of the laser beam 114. Further, the electrical current 124 may bedelivered to the laser source 112 according to an intensity modulation mode 404, such as when the determined optical power level 202 is greater than the threshold optical power level 202T. While delivering the electrical current 124 to the laser source 112 according to the intensity modulation mode 404, the amplitude 128 of the electrical current 124 is adjusted to adjust the optical power level 202 of the laser beam 114.

[0101] Optionally, the electrical current 124 delivered to the laser source 112 is limited based on a current temperature 138 of the laser source 112. For example, a maximum optical power level 202 may be limited based on the current temperature 138. When delivering the electrical current 124 to the laser source 112 according to the intensity modulation mode 404, the amplitude 128 of the electrical current 124 may be limited based on the current temperature 138 at the laser source 112. The temperature 138 at the laser source 112 may be determined based on the temperature of cooling fluid at the cooling system 140 of the laser engraver 100.

[0102] Referring to FIGS. 1 and 14, in some implementations, the gantry system 104 includes an encoder 142 that tracks the position of the laser head 106 relative to the bed 102. For example, one or more encoders 142 may sense movement of one or more motors 144 that adjust the position of the first rail 108 along the second rail 110 and the encoder 142 may sense movement of one or more motors 146 at the laser head 106 that adjusts position of the laser head 106 along the first rail 108. Thus, the encoder 142 provides a closed loop tracking system configured to track the head 106 as it is moved to any position or coordinate 1402 along a two-dimensional plane 1400 relative to the bed 102. Although described herein as tracking position of the head 106 along the two- dimensional plane 1400, it should be understood that the encoder 142 may track position of the head 106 in three-dimensional space in implementations where the laser head 106 moves vertically relative to the bed 102 (or the bed 102 moves vertically relative to the laser head 106). While the motor 146 is shown at the laser head 106 in FIG. 1, in various embodiments the motor for driving / adjusting the position of the laser head 106 may be disposed remote and away from the laser head 106, and a belt or other drive mechanism may be coupled between the motor 146 and the laser head 106 to impart movement of the laser head 106 along the first rail 108. Similarly, while motor(s) 144 are shown on thefirst rail 108, these motor(s) that drive movement of the first rail 108 along the second rails 110 may be disposed remote and away from the first rail 108, and one or more belts or other drive mechanisms may be coupled between the motor(s) and the first rail 108 to impart movement of the first rail 108 along the second rails 110.

[0103] Based on the coordinates 1402 of the head 106 relative to the bed 102, the control module 118 determines the position of the laser beam 114 relative to the bed 102. For example, the control module 118 determines the position of the laser beam 114 relative to the bed 102 to adjust the optical power 202 of the laser beam 114 according to the corresponding portion 16 of the graphical design 12 at the position 20 of the workpiece 10 at the position 1402 of the bed 102. In other words, based on the position 1402 of the head 106 relative to the bed 102, the control module 118 determines the corresponding portion 16 of the graphical design 12 that should be engraved onto the workpiece 10 with the head 106 at that position 1402.

[0104] Traditionally, the portion 16 of the graphical design 12 intended to be engraved at the workpiece 10 with the head 106 at a particular coordinate 1402 is determined based on a positional relationship between the coordinate 1402 and a true origin 1404 of the bed 102. For example, the bed 102 may include fences or rails along respective edges of the bed 102, with one corner of the bed (e.g., at an intersection of respective rails) defining the true origin 1404 of the bed 102. The workpiece 10 may engage the rails for locating the workpiece 10 relative to the true origin 1404 and the portions 16 of the graphic design 12 may be mapped to the coordinates 1402 of the bed 102 relative to the true origin 1404. In other words, each portion 16 of the graphical design 12 corresponds to a position 1402 along the bed 102 relative to the true origin 1404.

[0105] In the illustrated example, the head 106 is movable relative to the bed 102 between positions 1402. For example, the head 106 may be moved manually by the user or the head 106 may be moved via user input 1406, such as provided at a joystick or button or other suitable user actuatable input device 1408.

[0106] When the head 106 is moved by the user, the position 1402 of the head 106 may be used to define a new origin 1410 of the graphic design 12. The new origin 1410is transmitted to the control module 118 and the positions 1402 of each portion 16 of the graphical design 12 are adjusted relative to the true origin 1404 based on the new origin 1410. For example, the new origin 1410 of the graphic design 12 may correspond to a position 1402 of the head 106 near a central portion of the bed 102. Based on a change in coordinates 1402 from the true origin 1404 to the new origin 1410, the portions 16 of the graphical design 12 are adjusted to match. In other words, the graphical design 12 is snapped to the new location of the head 106.

[0107] As shown in FIGS. 1 and 14, a preview laser 148 or other suitable positional marker is operable to display the position 1402 of the head 106 relative to the bed 102 to the user. For example, the preview laser 148 directs a visible preview laser or light 150 (e.g., a red dot light) onto the bed 102 or workpiece 10 to show the position of the head 106 relative to the two-dimensional plane of the bed 102. The intersection of the preview laser 150 corresponds to the new origin 1410. Preferably, the preview laser 148 is disposed at the laser head 106 so that the preview light 150 is directed concentrically with the laser beam 114. However, the preview light 150 may be directed offset from the laser beam 114 by a known amount with the position 1402 of the head 106 adjusted accordingly. In some configurations, the laser head 106 emits the laser beam 114 at low power levels to provide the preview light 150 in lieu of implementing the dedicated preview laser 148.

[0108] Optionally, the user input 1406 that moves the laser head 106 may cause the preview laser 148 to direct the preview light 150 onto the bed 102 so that the user may view movement of the head 106 relative to the bed 102. Operation of the preview laser 148 may automatically adjust positions 1402 of the portions 16 of the graphic design 12 based on the new origin 1410.

[0109] When the positions 1402 of the portions 16 of the graphic design 12 are adjusted based on the new origin 1410, the positions 1402 may be adjusted in any suitable manner. For example, the graphic design 12 may be centered at the new origin 1410 or the graphic design 12 may be adjusted relative to the new origin 1410 so that the new origin 1410 is oriented at a corner of the graphic design 12 (e.g., a lower left corner of the graphic design 12).

[0110] FIG. 15 provides a flowchart of an exemplary arrangement of operations for a method 1500 of adjusting the graphical design 12 based on user movement of the head 106 relative to the bed 102 of the laser engraver 100. At operation 1502, the method 1500 includes receiving a graphical design 12 to be engraved onto the workpiece 10 by the laser engraver 100. Each portion 16 of a plurality of portions 16 of the graphical design 12 includes a position 1402 relative to a true origin 1404 of a bed 102 of the laser engraver 100.

[0111] At operation 1504, based on movement of the head 106 relative to the bed 102 to a new origin 1410 spaced from the true origin 1404, and for each portion 16 of the plurality of portions 16 of the graphical design 12, the method 1500 includes adjusting the position 1402 of the graphical design 12 relative to the true origin 1404 for the respective portion 16 based on the new origin 1410. At operation 1506, the method 1500 includes for each portion 16 of the graphic design 12, and with the head 106 positioned at the adjusted position 1402 relative to the new origin 1410, energizing a laser source 112 of the laser engraver 100 to direct the laser beam 114 from the laser head 106 onto the workpiece 10.

[0112] FIG. 16 is a schematic view of an example computing device 1600 that may be used to implement the systems and methods described in this document. The computing device 1600 is intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The components shown here, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and / or claimed in this document.

[0113] The computing device 1600 includes a processor 1610, memory 1620, a storage device 1630, a high-speed interface / controller 1640 connecting to the memory 1620 and high-speed expansion ports 1650, and a low speed interface / controller 1660 connecting to a low speed bus 1670 and a storage device 1630. Each of the components 1610, 1620, 1630, 1640, 1650, and 1660, are interconnected using various busses, and may be mounted on a common motherboard or in other manners as appropriate. Theprocessor 1610 can process instructions for execution within the computing device 1600, including instructions stored in the memory 1620 or on the storage device 1630 to display graphical information for a graphical user interface (GUI) on an external input / output device, such as display 1680 coupled to high speed interface 1640. In other implementations, multiple processors and / or multiple buses may be used, as appropriate, along with multiple memories and types of memory. Also, multiple computing devices 1600 may be connected, with each device providing portions of the necessary operations (e.g., as a server bank, a group of blade servers, or a multi-processor system).

[0114] The memory 1620 stores information non-transitorily within the computing device 1600. The memory 1620 may be a computer-readable medium, a volatile memory unit(s), or non-volatile memory unit(s). The non-transitory memory 1620 may be physical devices used to store programs (e.g., sequences of instructions) or data (e.g., program state information) on a temporary or permanent basis for use by the computing device 1600. Examples of non-volatile memory include, but are not limited to, flash memory and read-only memory (ROM) / programmable read-only memory (PROM) / erasable programmable read-only memory (EPROM) / electronically erasable programmable read-only memory (EEPROM) (e.g., typically used for firmware, such as boot programs). Examples of volatile memory include, but are not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), phase change memory (PCM) as well as disks or tapes.

[0115] The storage device 1630 is capable of providing mass storage for the computing device 1600. In some implementations, the storage device 1630 is a computer-readable medium. In various different implementations, the storage device 1630 may be a floppy disk device, a hard disk device, an optical disk device, or a tape device, a flash memory or other similar solid state memory device, or an array of devices, including devices in a storage area network or other configurations. In additional implementations, a computer program product is tangibly embodied in an information carrier. The computer program product contains instructions that, when executed, perform one or more methods, such as those described above. The information carrier isa computer- or machine-readable medium, such as the memory 1620, the storage device 1630, or memory on processor 1610.

[0116] The high speed controller 1640 manages bandwidth-intensive operations for the computing device 1600, while the low speed controller 1660 manages lower bandwidth-intensive operations. Such allocation of duties is exemplary only. In some implementations, the high-speed controller 1640 is coupled to the memory 1620, the display 1680 (e.g., through a graphics processor or accelerator), and to the high-speed expansion ports 1650, which may accept various expansion cards (not shown). In some implementations, the low-speed controller 1660 is coupled to the storage device 1630 and a low-speed expansion port 1690. The low-speed expansion port 1690, which may include various communication ports (e.g., USB, Bluetooth, Ethernet, wireless Ethernet), may be coupled to one or more input / output devices, such as a keyboard, a pointing device, a scanner, or a networking device such as a switch or router, e.g., through a network adapter.

[0117] The computing device 1600 may be implemented in a number of different forms, as shown in the figure. For example, it may be implemented as a standard server 1600a or multiple times in a group of such servers 1600a, as a laptop computer 1600b, or as part of a rack server system 1600c.

[0118] Various implementations of the systems and techniques described herein can be realized in digital electronic and / or optical circuitry, integrated circuitry, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which may be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0119] A software application (i.e., a software resource) may refer to computer software that causes a computing device to perform a task. In some examples, a software application may be referred to as an “application,” an “app,” or a “program.” Exampleapplications include, but are not limited to, system diagnostic applications, system management applications, system maintenance applications, word processing applications, spreadsheet applications, messaging applications, media streaming applications, social networking applications, and gaming applications.

[0120] These computer programs (also known as programs, software, software applications or code) include machine instructions for a programmable processor, and can be implemented in a high-level procedural and / or object-oriented programming language, and / or in assembly / machine language. As used herein, the terms “machine-readable medium” and “computer-readable medium” refer to any computer program product, non- transitory computer readable medium, apparatus and / or device (e.g., magnetic discs, optical disks, memory, Programmable Logic Devices (PLDs)) used to provide machine instructions and / or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term “machine-readable signal” refers to any signal used to provide machine instructions and / or data to a programmable processor.

[0121] The processes and logic flows described in this specification can be performed by one or more programmable processors, also referred to as data processing hardware, executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit). Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random access memory or both. The essential elements of a computer are a processor for performing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Computer readable media suitable for storing computer programinstructions and data include all forms of non-volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0122] To provide for interaction with a user, one or more aspects of the disclosure can be implemented on a computer having a display device, e.g., a CRT (cathode ray tube), LCD (liquid crystal display) monitor, or touch screen for displaying information to the user and optionally a keyboard and a pointing device, e.g., a mouse or a trackball, by which the user can provide input to the computer. Other kinds of devices can be used to provide interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user can be received in any form, including acoustic, speech, or tactile input. In addition, a computer can interact with a user by sending documents to and receiving documents from a device that is used by the user; for example, by sending web pages to a web browser on a user's client device in response to requests received from the web browser.

[0123] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. Accordingly, other implementations are within the scope of the following claims.

Claims

WHAT IS CLAIMED IS:

1. A computer-implemented method (700) when executed on data processing hardware (120) causes the data processing hardware (120) to perform operations comprising: receiving a graphical design (12) to be engraved onto a workpiece (10) by a laser engraver, the laser engraver configured to direct a laser beam from a head (106) of the laser engraver to engrave the graphical design (12) onto the workpiece (10); for each respective portion (16) of a plurality of portions of the graphical design (12): based on an intensity value (18) of the respective portion (16) of the graphical design (12), determining an optical power level (202) for the laser beam that causes the workpiece (10) to appear representative of the intensity value (18) when the laser beam is directed onto the workpiece (10) at the determined optical power level (202); and with the head (106) positioned relative to the workpiece (10) to direct the laser beam at a portion of the workpiece (10) corresponding to the respective portion (16) of the graphical design (12), energizing a laser source (114) of the laser engraver to direct the laser beam from the head (106) at the determined optical power level (202); based on the determined optical power level (202) being less than a threshold optical power level (202T), energizing the laser source (114) according to an enable modulation mode (402); and based on the determined optical power level (202) being greater than the threshold optical power level (202T), energizing the laser source (114) according to an intensity modulation mode (402).

2. The method (700) of claim 1, wherein energizing the laser source (114) comprises delivering an electrical current (124) from a power source (116) of the laser engraver to the laser source (114) according to a duty cycle.

3. The method (700) of claim 2, wherein:an intensity signal (130) along an intensity line to the power source (116) adjusts an amplitude (128) of the electrical current (124) from the power source (116); and an enable signal along an enable line to the power source (116) adjusts the duty cycle of the electrical current (124) from the power source (116).

4. The method (700) of claim 3, wherein energizing the laser source (114) according to the enable modulation mode (402) comprises adjusting the enable signal to adjust the duty cycle of the electrical current (124) from the power source (116) and to adjust the optical power level (202) to the determined optical power level (202) between a minimum optical power (202) and the threshold optical power level (202T).

5. The method (700) of claim 4, wherein, while energizing the laser source (114) according to the enable modulation mode (402), the intensity signal (130) is constant.

6. The method (700) of claim 3, wherein energizing the laser source (114) according to the intensity modulation mode (402) comprises adjusting the intensity signal (130) to adjust the amplitude (128) of the electrical current (124) from the power source (116) to adjust the optical power level (202) to the determined optical power level (202) between the threshold optical power (202T) and a maximum optical power level (202).

7. The method (700) of claim 6, wherein, while energizing the laser source (114) according to the intensity modulation mode (402), the enable signal is constant.

8. The method (700) of claim 6 or 7, wherein the maximum optical power level (202) is based on a temperature (138) at the laser source (114).

9. The method (700) of claim 8, wherein the temperature (138) at the laser source (114) is determined based on a temperature (138) of a cooling fluid of a cooling system10. The method (700) of any of claims 1-9, wherein the intensity value (18) of the respective portion (16) of the graphical design (12) comprises a pixel value (18) of the respective portion (16) of the graphical design (12).

11. The method (700) of any of claims 1-10, wherein determining the optical power level (202) for the respective portion (16) of the graphical design (12) comprises mapping, using a table, the intensity value (18) of the respective portion (16) of the graphical design (12) to the optical power level (202).

12. The method (700) of any of claims 1-11, wherein the laser source (114) comprises a CO2 laser tube.

13. A system (100) comprising: data processing hardware (120); and memory hardware (122) in communication with the data processing hardware (120), the memory hardware (122) storing instructions executed on the data processing hardware (120) that cause the data processing hardware (120) to perform operations comprising: receiving a graphical design (12) to be engraved onto a workpiece (10) by a laser engraver, the laser engraver configured to direct a laser beam from a head (106) of the laser engraver to engrave the graphical design (12) onto the workpiece (10); for each respective portion (16) of a plurality of portions of the graphical design (12): based on an intensity value (18) of the respective portion (16) of the graphical design (12), determining an optical power level (202) for the laser beam that causes the workpiece (10) to appear representative of the intensity value (18) when the laser beam is directed onto the workpiece (10) at the determined optical power level (202); and with the head (106) positioned relative to the workpiece (10) to direct the laser beam at a portion of the workpiece (10) corresponding to the respectiveportion (16) of the graphical design (12), energizing a laser source (114) of the laser engraver to direct the laser beam from the head (106) at the determined optical power level (202); based on the determined optical power level (202) being less than a threshold optical power level (202), energizing the laser source (114) according to an enable modulation mode (402); and based on the determined optical power level (202) being greater than the threshold optical power level (202), energizing the laser source (114) according to an intensity modulation mode (402).

14. The system (100) of claim 13, wherein energizing the laser source (114) comprises delivering an electrical current (124) from a power source (116) of the laser engraver to the laser source (114) according to a duty cycle.

15. The system (100) of claim 14, wherein: an intensity signal (130) along an intensity line to the power source (116) adjusts an amplitude (128) of the electrical current (124) from the power source (116); and an enable signal along an enable line to the power source (116) adjusts the duty cycle of the electrical current (124) from the power source (116).

16. The system (100) of claim 15, wherein energizing the laser source (114) according to the enable modulation mode (402) comprises adjusting the enable signal to adjust the duty cycle of the electrical current (124) from the power source (116) and to adjust the optical power level (202) to the determined optical power level (202) between a minimum optical power (202) and the threshold optical power level (202).

17. The system (100) of claim 16, wherein, while energizing the laser source (114) according to the enable modulation mode (402), the intensity signal (130) is constant.

18. The system (100) of claim 15, wherein energizing the laser source (114) according to the intensity modulation mode (402) comprises adjusting the intensity signal (130) to adjust the amplitude (128) of the electrical current (124) from the power source (116) to adjust the optical power level (202) to the determined optical power level (202) between the threshold optical power (202) and a maximum optical power level (202).

19. The system (100) of claim 18, wherein, while energizing the laser source (114) according to the intensity modulation mode (402), the enable signal is constant.

20. The system (100) of claim 18 or 19, wherein the maximum optical power level (202) is based on a temperature (138) at the laser source (114).

21. The system (100) of claim 20, wherein the temperature (138) at the laser source (114) is determined based on a temperature (138) of cooling fluid of a cooling system (140) of the laser engraver.

22. The system (100) of any of claims 13-21, wherein the intensity value (18) of the respective portion (16) of the graphical design (12) comprises a pixel value (18) of the respective portion (16) of the graphical design (12).

23. The system (100) of any of claims 13-22, wherein determining the optical power level (202) for the respective portion (16) of the graphical design (12) comprises mapping, using a table, the intensity value (18) of the respective portion (16) of the graphical design (12) to the optical power level (202).

24. The system (100) of any of claims 13-23, wherein the laser source (114) comprises a CO2 laser tube.

Images