High resolution temperature control at the sprue bushing-mold interior interface for injection molding of chalcogenide glasses

Abstract

A method for forming a precision optical element by injection molding is disclosed. The method includes: heating a chalcogenide glass to form a glass melt; and guiding the glass melt along a channel from an injection device into a mold cavity of a mold, the mold cavity negatively defining the precision optical element. The channel includes a nozzle channel defined by the injection device, a runner channel defined by the mold interior of the mold, and a runner channel defined by a heated runner bushing disposed in the mold. The method further includes: solidifying the glass melt in the mold to form the precision optical element and a runner element corresponding to the runner channel; and then ejecting the precision optical element and the runner element from the mold. The method further includes heating a first portion of the runner channel adjacent to the runner channel such that the solidified glass in the first portion completely detaches from the first portion.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 603,408, filed November 28, 2023, pursuant to 35 USC § 119, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This disclosure relates to glass injection molding. Specifically, this disclosure relates to processes and equipment for injection molding chalcogenide glasses. Background Technology

[0004] Injection molding machines used for manufacturing molded parts from polymers typically employ a two-part mold in which a mold cavity is formed. These two parts can be separated to remove the molded part. The polymer molding material is heated to a molten state and forced through a passage consisting of an injection nozzle, a runner bushing, a runner, and a gate into the mold cavity. Once the mold cavity is filled with molten material, it is cooled, causing the molded part to solidify. The two mold parts are then opened, and the molded part is removed in the usual manner. This process requires a hot / cold junction at a point along the passage, where on one side the material solidifies along the cooled portion, while on the other side the material remains molten. This hot / cold junction is typically provided by a runner bushing having an inlet orifice and a smaller tapered orifice intersecting the inlet orifice. The inlet orifice forms part of the hot portion of the passage, and the tapered orifice forms part of the cold portion of the passage. This tapered orifice leads to the runner portion of the passage, which leads directly into the mold cavity.

[0005] After the molded part cools, material from the runner and tapered bore adheres to the molded part. When the molded part is ejected, the material in the tapered bore is typically configured to be pulled out of the runner bushing and ejected along with the molded part and runner. However, the ease with which the material pulled out of the runner bushing detaches depends on the type of material and other processing parameters, such as the temperature of the runner bushing. The temperature of the runner bushing depends on its type. Generally, there are two types of runner bushings: hot runner bushings or heated runner bushings; and cold runner bushings. Heated runner bushings include some form of supplemental heating, such as external heating coils positioned around the periphery of the runner bushing. This supplemental heating allows the temperature of the hot runner bushing to be higher than the mold area where the hot runner bushing is mounted. In contrast, cold runner bushings do not have any supplemental heating, so their temperature is the same as the temperature of the mold area where the cold runner bushing is mounted.

[0006] The applicant has developed a process and equipment for injection molding chalcogenide glasses. Chalcogenide glasses are non-oxide glasses comprising one or more of chalcogen elements (e.g., Group VIA elements, CAS nomenclature) sulfur (S), selenium (Se), and tellurium (Te), as well as one or more metals and / or half-metals (e.g., metalloids). While the glass transition temperature of chalcogenide glasses is fairly compatible with polymer-based injection molding systems, the steep viscosity profile of chalcogenide glasses (like most glasses) means that even small temperature changes can have a significant impact on the glass's flowability. This temperature sensitivity of chalcogenide glasses exists throughout the injection molding system, from the feed hopper to the mold cavity.

[0007] One problem with injection-molded chalcogenide glasses involves the transition from the injection system to the mold at the runner bushing. Chalcogenide glasses are very brittle and hard near their transition temperatures, leading to breakage and failure to detach due to the lack of supplemental heating in existing cold runner bushings. Existing heated runner bushings may lack the thermal control and structural properties required to minimize turbulence-induced defects (such as excessive air bubbles within the molded part) and to fully allow for non-destructive material detachment from the runner.

[0008] Therefore, to overcome the above problems, it would be advantageous to develop systems and methods for injection molding chalcogenide glass using heated runner bushings, wherein high-resolution temperature control is achieved at the runner bushing-mold interior interface. Summary of the Invention

[0009] The following summary is a brief description of certain aspects of this disclosure. The summary should not be considered as a limitation on the breadth, scope, or applicability of this disclosure.

[0010] According to aspect (1), a method for forming precision optical elements by injection molding is provided. The method comprises: heating chalcogenide glass particles in an injection apparatus to form a glass melt, wherein 10% of the chalcogenide glass… 4.0 P temperature is 500°C or lower and in the range of 1,000 sec -1 Up to 10,000 sec -1It exhibits anti-crystallization properties at shear rates; the glass melt is guided along a channel from the injection device into a mold cavity of a mold, the mold cavity negatively defining the precision optical element, the channel comprising: a nozzle channel through which the glass melt is guided from the injection device, the nozzle channel being defined by the injection device; a runner channel through which the glass melt is guided into the mold cavity, the runner channel being defined by the mold interior of the mold; and a sprue channel through which the glass melt is guided from the nozzle channel to the runner channel, the sprue channel being defined by a heated sprue bushing, the heated sprue bushing... The glass melt is solidified inside the mold and (i) the solidified glass forms the precision optical element in the mold cavity and (ii) the solidified glass forms a runner element in the runner channel; the precision optical element and the runner element are ejected from the mold; and a first runner channel portion near the runner channel is heated with a first heater such that when the runner element is ejected from the mold, the solidified glass in the first runner channel portion is configured to completely detach from the first runner channel portion and be ejected together with the runner element.

[0011] According to aspect (2), a method of aspect (1) is provided, wherein the heated runner bushing has a first runner bushing portion defining the first runner channel portion, and wherein heating the first runner channel portion comprises changing the heating rate of the first heater such that, at the time of ejection, the first runner bushing portion has a first set point temperature.

[0012] According to aspect (3), the method of aspect (2) is provided, which further includes heating a second injection channel portion of the injection channel near the nozzle channel with a second heater, such that the glass melt in the second injection channel portion remains liquid.

[0013] According to aspect (4), a method of aspect (3) is provided, wherein the injection channel includes a narrowing transition portion that separates the first injection channel portion from the second injection channel portion.

[0014] According to aspect (5), a method of aspect (4) is provided, wherein the heated runner bushing has a second runner bushing portion defining the second runner channel portion, and wherein heating the second runner channel portion includes maintaining the second runner bushing portion at a second set point temperature.

[0015] According to aspect (6), the method of aspect (5) is provided, wherein the first setpoint temperature is greater than or equal to the second setpoint temperature.

[0016] According to aspect (7), the method of aspect (5) is provided, wherein the first setpoint temperature is at least 10°C higher than the second setpoint temperature.

[0017] According to aspect (8), a method of any one of aspects (1) to (7) is provided, wherein the mold comprises (i) a first half mold whose position is fixed relative to the injection device and (ii) a second half mold configured to translate relative to the first half mold, the heated runner bushing being disposed in the first half mold.

[0018] According to aspect (9), a method of aspect (8) is provided, wherein the second half mold is configured to translate between (i) a mold-locking position during the guiding and solidification and (ii) a mold-opening position during the ejection, wherein in the mold-locking position the second half mold is pressed against the first half mold, and in the mold-opening position the second half mold is spaced apart from the first half mold.

[0019] According to aspect (10), a method of any one of aspects (1) to (9) is provided, wherein the injection channel is configured to be continuous along its entire length between the outside of the mold and the inside of the mold.

[0020] According to aspect (11), a method of any one of aspects (1) to (10) is provided, which further comprises: establishing an injection volume of the glass melt in the injection device under a first pressure before the induction; and after establishing the injection volume, applying a second pressure greater than the first pressure to the injection volume in the injection device for a first duration to degas the glass melt.

[0021] According to aspect (12), an injection molding system is provided. The injection molding system includes: an injection device configured to heat chalcogenide glass particles to form a glass melt, wherein 10 of the chalcogenide glass... 4.0 P temperature is 500°C or lower and in the range of 1,000 sec -1 Up to 10,000 sec -1The injection device exhibits anti-crystallization properties at shear rates of [specific value missing]. It includes a nozzle defining a nozzle channel through which the glass melt is guided from the injection device; a mold having an exterior and an interior spaced apart from the exterior, the interior defining a mold cavity and runner channels, the glass melt being guided into the mold cavity through the runner channels, the mold cavity being configured to negatively define a precision optical element; a heated runner bushing extending through the mold from the exterior to the interior, defining a runner channel through which the glass melt is guided from the nozzle channel to the runner channels; and a controller configured to operate the injection mold. The system is configured to: guide the molten glass from the injection device along the nozzle channel, the runner channel, and the flow channel into the mold cavity; solidify the molten glass within the mold cavity to (i) form the precision optical element from the solidified glass in the mold cavity, and (ii) form a flow channel element from the solidified glass in the flow channel, and eject the precision optical element and the flow channel element from the mold; and a first heater configured to heat a first runner channel portion of the runner channel adjacent to the flow channel, such that when the flow channel element is ejected from the mold, the solidified glass within the first runner channel portion is configured to completely detach from the first runner channel portion and be ejected together with the flow channel element.

[0022] According to aspect (13), an injection molding system of aspect (12) is provided, wherein: the heated runner bushing has a first runner bushing portion defining a first runner channel portion, the injection system further includes a first sensor configured to detect a first temperature of the first runner bushing portion, the controller is configured to: (i) receive the first temperature from the first sensor, (ii) compare the first temperature with a first setpoint temperature, and (iii) generate a first command based on the comparison, and the first heater is configured to receive the first command and change the heating rate of the first heater such that, at the time of ejection, the first runner bushing portion has the first setpoint temperature.

[0023] According to aspect (14), an injection molding system of aspect (13) is provided, which further includes a second heater configured to heat a second injection channel portion of the injection channel near the nozzle channel, such that the glass melt in the second injection channel portion remains liquid.

[0024] According to aspect (15), an injection molding system of aspect (14) is provided, wherein the injection channel includes a narrowing transition portion separating the first injection channel portion from the second injection channel portion.

[0025] According to aspect (16), an injection molding system of aspect (15) is provided, wherein: the heated runner bushing has a second runner bushing portion defining a second runner channel portion, the injection system further includes a second sensor configured to detect a second temperature of the second runner bushing portion, the controller is configured to: (i) receive the second temperature from the second sensor, (ii) compare the second temperature with a second setpoint temperature, and (iii) generate a second command based on the comparison, and the second heater is configured to receive the second command and maintain the second runner bushing portion at the second setpoint temperature.

[0026] According to aspect (17), an injection molding system of aspect (16) is provided, wherein the first setpoint temperature is greater than or equal to the second setpoint temperature.

[0027] According to aspect (18), an injection molding system of aspect (16) is provided, wherein the first set point temperature is at least 10°C higher than the second set point temperature.

[0028] According to aspect (19), an injection molding system of any one of aspects (12) to (18) is provided, wherein the mold comprises (i) a first half mold whose position is fixed relative to the injection device and (ii) a second half mold configured to translate relative to the first half mold, wherein the heated runner bushing is disposed in the first half mold.

[0029] According to aspect (20), an injection molding system of aspect (19) is provided, wherein the second half mold is configured to translate between (i) a locked position when the glass melt is guided from the injection device and solidified inside the mold and (ii) an open position when the precision optical element and the runner element are ejected from the mold, wherein in the locked position the second half mold is pressed against the first half mold and in the open position the second half mold is spaced apart from the first half mold.

[0030] According to aspect (21), an injection molding system of any one of aspects (12) to (20) is provided, wherein the injection channel is configured to be continuous along its entire length between the outside of the mold and the inside of the mold. Attached Figure Description

[0031] Figure 1It is a schematic representation of an injection molding system configured to form precision optical elements from chalcogenide glass;

[0032] Figure 2 yes Figure 1 A schematic cross-sectional view of the injection unit and the fixed half mold of the injection molding system;

[0033] Figure 3A yes Figure 2 An enlarged schematic cross-sectional view of the fixed half-mold, showing a heated runner bushing with a first heater configuration;

[0034] Figure 3B yes Figure 3A A front view of the fixed half-mold, showing its position at arrow 302 ( Figure 3A The central area in the direction of );

[0035] Figure 4 yes Figure 2 An enlarged schematic cross-sectional view of the fixed half-mold, showing a heated runner bushing with a second heater configuration; and

[0036] Figure 5 yes Figure 2 An enlarged schematic cross-sectional view of the fixed half-mold, showing a heated sprue bushing with heat-insulating components. Detailed Implementation

[0037] To facilitate an understanding of the principles of this disclosure, reference will now be made to embodiments illustrated in the accompanying drawings and described in the following written description. It should be understood that this disclosure is not intended to limit the scope of the disclosure. It should be further understood that this disclosure includes any changes and modifications to the illustrated embodiments, and includes further applications of the principles disclosed herein that would commonly occur to those skilled in the art to which this disclosure pertains.

[0038] As used herein, when used for a list of two or more items, the term "and / or" means that any one of the listed items may be used alone, or any combination of two or more of the listed items may be used. For example, if a composition is described as containing components A, B, and / or C, the composition may contain only A; only B; only C; a combination of A and B; a combination of A and C; a combination of B and C; or a combination of A, B, and C.

[0039] In this document, relational terms such as first and second, top and bottom are used only to distinguish one entity or action from another, and do not necessarily require or imply any actual such relationship or order between such entities or actions.

[0040] As used herein, the term "about" means that a quantity, size, formulation, parameter, and other quantity and characteristic is not and does not need to be precise, but may be approximate and / or larger or smaller as required, reflecting tolerances, conversion factors, rounding, measurement errors, and other factors known to those skilled in the art. When the term "about" is used to describe a value or range endpoint, this disclosure should be understood to include the specific value or endpoint mentioned. Regardless of whether a numerical or range endpoint in the specification is described with "about," the numerical or range endpoint is intended to include two embodiments: one modified by "about" and one not modified by "about." It should be further understood that each range endpoint is meaningful whether it is related to or not related to another endpoint.

[0041] Concentration, quantity, and other numerical data may be expressed or presented in range format herein. It should be understood that such range format is used solely for convenience and brevity, and therefore should be flexibly interpreted to include not only the numerical values ​​explicitly stated as the limits of the range, but also all individual numerical values ​​or subranges encompassed within said range, as if each numerical value and subrange were explicitly stated. For example, a numerical range of “about 1 to about 5” should be interpreted to include not only the explicitly stated values ​​of about 1 to about 5, but also the individual values ​​and subranges within the indicated range. Thus, this numerical range includes individual values ​​such as 2, 3, and 4, and subranges such as 1-3, 2-4, 3-5, as well as 1, 2, 3, 4, and 5 individually. The same principle applies to ranges that list only one numerical value as a minimum or maximum value. Furthermore, this interpretation should apply regardless of how broad the range is or what characteristics it describes.

[0042] Unless defined elsewhere in association with a particular term or phrase, the terms “substantially,” “basically,” and their variations as used herein are intended to indicate that the described feature is equal to or approximately equal to a value or description. For example, a “substantially flat” surface is intended to mean a flat or substantially flat surface. Furthermore, “substantially” is intended to mean that two values ​​are equal or approximately equal. In some embodiments, “substantially” may mean values ​​that differ from each other by about 10%, such as values ​​that differ from each other by about 5%, or values ​​that differ from each other by about 2%.

[0043] The directional terms used in this article, such as up, down, right, left, front, back, top, bottom, above, below, etc., are for reference only to the drawn diagrams and are not intended to imply absolute orientation.

[0044] As used herein, the terms “the”, “a / an” mean “at least one”, and should not be limited to “only one” unless explicitly indicated otherwise. Thus, for example, unless the context explicitly indicates otherwise, references to “component” include embodiments having two or more such components.

[0045] As used herein, the term "chalcogenide glass" refers to a non-oxide glass comprising one or more of the chalcogenide elements sulfur (S), selenium (Se), and tellurium (Te), as well as one or more metals and / or half-metals (e.g., metalloids). Chalcogenide glasses are generally transparent to electromagnetic radiation (light) in the infrared (IR) spectral range of 500–20,000 nm (0.5–20 µm).

[0046] As used herein, the terms “hot melt processing,” “hot melt process,” or similar terms refer to any process involving heating chalcogenide glass above its glass transition temperature (Tg) and applying pressure to the (molten) chalcogenide glass to form it into a glass article of interest. Examples of hot melt processing include injection molding, extrusion, and transfer molding.

[0047] As used herein, the terms "10,000 Poisson temperature", "10,000 P temperature", and "10" are used interchangeably with "10". 4.0 "P temperature" or similar terminology refers to the temperature at which the viscosity of glass is 10,000 P. 4.0 The temperature P is an approximate temperature estimate for glass processing based on the techniques disclosed herein. 10 4.0 The temperature P varies depending on the materials in the glass and can be determined using techniques known in the art. In embodiments, the 10 P temperature of the chalcogenide glass disclosed herein... 4.0 The temperature P is 500°C or lower, or preferably 400°C or lower, which allows these glasses to be injection molded using equipment typically configured for hot-melt processing of polymer materials.

[0048] As used herein, the term "crystallization" refers to the formation of crystals or solid phases in which the components of a material are arranged in a highly ordered microstructure. As used herein, the terms "shear thickening" and "shear-induced crystallization" refer to the crystallization phenomenon where the viscosity of a (fluid) material increases when subjected to (increasing) shear stress. As used herein, the term "shear thinning" refers to the behavior of a (fluid) material where its viscosity decreases when subjected to (increasing) shear stress. Both shear thickening and shear thinning can occur at isothermal conditions. In the embodiments, crystallization is undesirable in the chalcogen glasses and methods disclosed herein. In the embodiments, the chalcogen glasses disclosed herein exhibit resistance to shear thickening during processing, particularly during hot-melt processing, during which the chalcogen glasses (e.g., molten chalcogen glasses) can withstand temperatures common to such hot-melt processing (e.g., from about 250°C to about 500°C or higher) for about 1,000 seconds. -1 From approximately 10,000 sec -1 The shear rate within the range.

[0049] As used in this article, the material's "glass transition temperature" (T) g (T) refers to the temperature at which an amorphous material undergoes a glass transition. Below T... g At this temperature, the material exists in a solid state, while at temperatures above T... g At that time, the material exists in a molten state. If the material exists in a crystalline state, then T g Below the melting temperature of the material in its crystalline state.

[0050] Now for reference Figure 1 , 2 3A and 3B describe an injection molding system 100 configured to form precision optical elements from chalcogenide glass. The injection molding system 100 includes an injection unit 200, a mold 300, a clamping system 400, and a controller 500. The injection unit 200 includes an injection device 204 configured to plasticize the chalcogenide glass and inject the plasticized chalcogenide glass into the mold 300. In embodiments, the injection device 204 may be configured to plasticize and inject the chalcogenide glass using a "plunger" process, a "screw" process, or a "screw-plunger" process.

[0051] In a plunger process, each stroke of the piston pushes unmelted material into a heated cylinder, which in turn forces molten material at the front of the cylinder to be ejected through a nozzle and into a mold having one or more cavities configured to conform to the shape of the part to be molded. In a screw process, unmelted granular material is conveyed forward through a heated cylinder by the rotation of a helical element. The material is transformed into a viscous melt by friction and heat conducted from the cylinder. The molten material at the front of the screw is injected into the mold by the translational / reciprocating motion of the screw itself. Similar to the mold in the plunger process, the mold in the screw process also has one or more cavities configured to conform to the shape of the part to be molded.

[0052] Now for reference Figure 2 An embodiment of an injection apparatus 204 is shown, which is configured to use a screw-plump process to plasticize and inject chalcogenide glass. For example... Figure 2As shown, unmelted granular material is conveyed forward through a heated cylinder 208 by the rotation of a helical element or screw 212. Similar to the screw process, the material is transformed into a viscous melt by the frictional force generated by the screw 212 and the heat conducted from the cylinder 208. However, in the screw-plunger process, the screw 212 is essentially stationary and is not used to inject the viscous melt into the mold 300. Instead, the molten material in front of the screw is guided by the screw 212 to a separate cylinder 216 until the piston 220 is compressed backward by a predetermined injection volume of viscous melt in the separate cylinder 216. The piston 220 is then actuated to inject the molten material into the mold 300. In the exemplary embodiment, the screw-plunger type injection molding system is preferred because the screw-plunger process offers better mixing and process consistency. In one embodiment, the injection device 204 includes a nozzle 232 that defines a nozzle channel 236 through which molten glass is configured to be guided or discharged from the injection device 204.

[0053] Now for reference Figure 1 The injection device 200 includes a feeding device 224, which is configured to feed through a feeding port 228 in the injection device 204. Figure 2 The chalcogenide glass particles are delivered or fed into the injection unit 204. In an embodiment, the feed unit 224 is configured to condition the chalcogenide glass particles before delivery to the injection unit 204. For example, the chalcogenide glass particles may be configured to be dried at the bottom of the feed unit 224 at a drying temperature (e.g., between about 100°C and about 140°C, between about 110°C and about 130°C, or about 120°C) for a certain drying duration (e.g., about 5 hours, about 4 hours, about 3 hours, or about 2 hours). In an embodiment, the chalcogenide glass particles may be degassed in the feed unit 224 before delivery to the injection unit 204.

[0054] The injection device 204 is configured to heat the chalcogenide glass particles to form a glass melt. In an embodiment, the chalcogenide glass comprises 10 4.0 P temperature is 500°C or lower (e.g., 400°C or lower) and in the range of 1,000 sec -1 Up to 10,000 seconds -1 A glass composition exhibiting anti-crystallization properties at shear rates of 500°C or lower. A temperature of 500°C or lower corresponds to the approximate maximum operating temperature of the injection molding system 100 according to the embodiment. A temperature of 500°C or lower also corresponds to the approximate maximum operating temperature of commercially available injection molding equipment. At 1,000 sec... -1 Up to 10,000 sec-1 The range of shear rates corresponds to the approximate shear rates that the glass melt can be exposed during injection molding using the injection molding system 100 according to the embodiment. Examples of chalcogenide glass compositions that can be injection molded using the injection molding system 100 are disclosed in U.S. Patent No. 7,116,888 B1, published October 3, 2006, and U.S. Patent No. 10,519,061 B2, published December 31, 2019, the contents of each of which are incorporated herein by reference in their entirety.

[0055] Now for reference Figure 1 , 2 3A and 3B describe the mold 300 and the clamping system 400. In an embodiment, the mold 300 includes a first mold half 304 fixed or stationary relative to the injection unit 200 and a second mold half 308 configured to translate relative to the first mold half 304. The first mold half 304 may be interchangeably referred to as half A or surface A, and the second mold half 308 may be interchangeably referred to as half B or surface B. The clamping system 400 includes a first pressure plate 404 fixed or stationary relative to the injection unit 200 and a second pressure plate 408 configured to translate relative to the first pressure plate 404. The first (stationary) mold half 304 is fixed to the first (stationary) pressure plate 404, and the second (movable) mold half 308 is fixed to the second (movable) pressure plate 408.

[0056] The mold-locking system 400 further includes a drive system 412 configured to move a second pressure plate 408, which in turn moves a second mold half 308 between a locked position and an open position, in which the locked position the second mold half 308 contacts the first mold half 304, such as... Figure 1 As shown, in the mold-opening position, the second mold half 308 is spaced apart from the first mold half 304. When the second mold half 308 is in the mold-locking position, the mold-locking system 400 is further configured to press the second mold half 308 against the first mold half 304 with sufficient force to generate the high pressure required to inject molten material into the mold 300 during the injection molding cycle, as described later in this disclosure. In an exemplary embodiment, the drive system is a hydraulic cylinder, such as... Figure 1 As shown, the hydraulic cylinder is configured to generate high pressure between the first mold half 304 and the second mold half 308 during the injection molding cycle. Other drive systems may be used in other embodiments.

[0057] Now for reference Figure 2 , 3A And 3B, each of the first half mold 304 and the second half mold 308 has a mold exterior 312 and a mold interior 316 spaced apart from the mold exterior 312. The mold interior 316 includes a surface of the mold 300, said surface being perpendicular to the parting line or parting plane 320. Figure 1 The parting line or parting plane is formed when the second half of the mold 308 contacts / presses against the first half of the mold 304 in the mold-locking position. In the illustrated embodiment, the mold interior 316 of the first half of the mold 304 is configured to define a mold cavity 324 and a runner channel 328, through which the molten glass is configured to be guided into the mold cavity 324 during an injection molding cycle. Once the molten glass solidifies in the mold cavity 324, the mold cavity is configured to negatively define a precision optical element.

[0058] In an embodiment, the precision optical element comprises a glass body molded from chalcogenide glass added to an injection molding system 100. The glass body is configured to define the structure of the precision optical element. In an embodiment, the (molded) glass body has one or more surfaces that are smooth (e.g., surface roughness ≤ 10 nm Ra), have simple or complex profiles (e.g., concave, convex, and / or true prismatic profiles), and / or have precise surface features in the micrometer (e.g., < 500 µm) to submicrometer size range, which is required for image forming or transmission applications. In an embodiment, the precision optical element may be a lens, microlens, microlens array, prism, coupler, sensor, diffraction grating, surface relief diffuser, Fresnel lens, optical fiber, or a precision optical device comprising multiple optical elements. In an exemplary embodiment, the precision optical element is a lens.

[0059] Although only one mold cavity 324 and one runner channel 328 are depicted in the figure, it should be understood that other embodiments may have any number and configuration of mold cavities and runners. Similarly, it should be understood that the first half mold 304 and / or the second half mold 308 may include additional features for facilitating the injection molding of precision optical components, such as runners, gates, ejector pins, vents, movable or fixed inserts, etc.

[0060] Refer again Figure 1 , 2According to 3A and 3B, the injection molding system 100 further includes a heated runner bushing 110 disposed in a first mold half 304. The heated runner bushing 110 has a body 114 comprising a head portion 118 and an elongated portion 122 extending from the head portion 118. In embodiments, the head portion 118 and the elongated portion 122 have cylindrical peripheries arranged substantially concentrically with each other. In such embodiments, the diameter of the head portion 118 may be larger than the diameter of the elongated portion 122, such that the head portion 118 defines a flange 122. The first mold half 304 may have a through-hole extending between a mold exterior 312 and a mold interior 316, wherein a countersunk hole opens to the mold exterior 312. The flange 126 is configured to abut the bottom of the countersunk hole 130 to position the heated runner bushing 110 against the first mold half 304. The head portion 118 may have a contact surface 132, which is configured to adjoin the nozzle 232 of the injection device 204. In an embodiment, as... Figure 3A As shown, the contact surface defines a concave spherical recess, which is configured to self-align the nozzle 232 with the heated injection channel bushing 110.

[0061] like Figure 3A As best shown, a heated runner bushing 110 extends from the mold exterior 312 to the mold interior 316 through the mold 300 (e.g., a first half-mold 304). The body 114 of the heated runner bushing 110 is configured to define a runner channel 134 through which molten glass is guided from a nozzle channel 236 to a runner channel 328. The heated runner bushing 110 has a first runner bushing portion 138 that defines a first runner channel portion 140 of the runner channel 134. The first runner channel portion 140 is adjacent to (e.g., fluidly connected to) the runner channel 328. The heated runner bushing 110 also has a second runner bushing portion 142 that defines a second runner channel portion 144 of the runner channel 134. The second runner channel portion 144 is adjacent to (e.g., fluidly connected to) the nozzle channel 236.

[0062] The injection channel 134 includes a narrowing transition portion 148 that separates the first injection channel portion 140 from the second injection channel portion 144. Since the first injection bushing portion 138 and the second injection bushing portion 142 respectively define the first injection channel portion 140 and the second injection channel portion 144, the narrowing transition portion 148 correspondingly separates the first injection bushing portion 138 from the second injection bushing portion 142. Figure 3AIn the diagram, a dashed line positioned at the narrowing transition 148 and oriented substantially perpendicular to the central axis of the runner channel 134 illustrates the separation between the first runner bushing portion 138 (e.g., defining the first runner channel portion 140) and the second runner bushing portion 142 (e.g., defining the second runner channel portion 144). In an embodiment, the narrowing transition 148 comprises a region where the diameter of the runner channel 134 decreases. The narrowing transition 148 can be located anywhere along the runner channel 134, but it is preferably located at the midpoint of the runner channel or closer to the runner channel 328 than the midpoint. In an exemplary embodiment, the narrowing transition 148 is located close to the runner channel 328, separated by approximately 20%, 15%, 10%, 5%, or less of the total length of the runner channel 134.

[0063] In an embodiment, the runner channel 134 is configured to be continuous along its entire length between the mold exterior 312 and the mold interior 316. As used herein, "continuous" means that the surface defining the runner channel 134 is smooth and free of discontinuities that could cause turbulence as the glass melt flows through it. For example, the runner channel 134 is continuous when it is entirely defined by the entire area of ​​the heated runner bushing 110 (e.g., without threaded tips). The continuity and smoothness of the runner channel 134 can affect the number of air bubbles contained in the injection-molded part formed from chalcogenide glass. More specifically, discontinuous and / or rough surfaces within the runner channel 134 can increase the number of air bubbles in the injection-molded part, potentially reducing infrared transmittance through the injection-molded part.

[0064] Now for reference Figure 2 and 3A The injection molding system 100 further includes a first heater 150 configured to heat a first runner channel portion 140 of the runner channel 134 adjacent to the runner channel 328. In an embodiment, the first heater 150 is configured to heat the first runner channel portion 140 such that when the runner element is ejected from the mold 300 (as described later in this disclosure), the solidified glass in the first runner channel portion 140 is configured to completely detach from the first runner channel portion and be ejected together with the runner element.

[0065] The first heater 150 can be positioned to contact the periphery of the elongated portion 122 of the heated runner bushing 110, such that the first heater (completely) surrounds the first runner bushing portion 138 and (completely) surrounds the corresponding portion of the second runner bushing portion 142 associated with the elongated portion 122. The first heater 150 can heat the first runner bushing portion 138, thereby heating the corresponding first runner channel portion 140 defined by the first runner bushing portion 138. The first heater 150 can also heat the corresponding portion of the second runner bushing portion 142 associated with the elongated portion 122, thereby heating the corresponding second runner channel portion 144 defined by the corresponding portion of the second runner bushing portion 142.

[0066] Still referencing Figure 2 and 3A The injection molding system 100 may further include a second heater 154 configured to heat a second runner channel portion 144 of the runner channel 134 near the nozzle channel 236. In an embodiment, the second heater 154 is configured to heat the second runner channel portion 144 such that the molten glass in the second runner channel portion 144 remains liquid, for example, throughout the entire injection molding cycle. In an embodiment, the first heater 150 and the second heater 154 cooperate to heat the second runner channel portion 144 such that the molten glass in the second runner channel portion 144 remains liquid, for example, throughout the entire injection molding cycle.

[0067] The second heater 154 can be positioned to contact the periphery of the head portion 118 of the heated runner bushing 110, such that the second heater (completely) surrounds the corresponding portion of the second runner bushing portion 142 associated with the head portion 118. The second heater 154 can heat the corresponding portion of the second runner bushing portion 142 associated with the head portion 118, thereby heating the corresponding second runner channel portion 144 defined by the corresponding portion of the second runner bushing portion 142. In embodiments, the first heater 150 and the second heater 154 can be controlled independently of each other, as described later in this disclosure. In such embodiments, the heated runner bushing 110 has two temperature control zones.

[0068] Figure 4This is an enlarged schematic cross-sectional view of the first (fixed) half mold 304, showing heated runner bushings 110 with different heater configurations. For example, a first heater 150a may be positioned to contact the periphery of a portion of the elongated portion 122 of the heated runner bushing 110, such that the first heater only (completely) surrounds the first runner bushing portion 138. A second heater 154a may be positioned to contact the periphery of a different portion of the elongated portion 122 of the heated runner bushing 110, such that the second heater only (completely) surrounds the corresponding portion of the second runner bushing portion 142 associated with the elongated portion 122. The second heater 154a may also be positioned to contact the periphery of the head portion 118 of the heated runner bushing 110, such that the second heater (completely) surrounds the corresponding portion of the second runner bushing portion 142 associated with the head portion 118.

[0069] exist Figure 4 In the illustrated configuration, the first heater 150a is configured to specifically heat the first gutter bushing portion 138, thereby heating the corresponding first gutter channel portion 140 defined by the first gutter bushing portion 138. The second heater 154a is configured to specifically heat the second gutter bushing portion 142 (e.g., the corresponding portion of the second gutter bushing 142 associated with the head portion 118 and the elongated portion 122), thereby heating the corresponding second gutter channel portion 144 defined by the second gutter bushing portion 142. In the embodiment, similar to Figure 2 and 3A First heater 150 and second heater 154, Figure 4 The first heater 150a and the second heater 154a can be controlled independently of each other. In this embodiment, the heated runner bushing 110 has two temperature control zones.

[0070] Reference Figure 4 In another heater configuration described, the second heater 154a, positioned to contact the periphery of the head portion 118 of the heated runner bushing 110, is further configured as a third heater 158, which can be controlled independently of the first heater 150a and the second heater 154a. In this configuration, the heated runner bushing 110 has three temperature control zones. (Reference) Figure 4 The configuration shown and described enables high-resolution temperature control of the first injection channel portion 140 of the injection channel 134, which can further facilitate the detachment of the solidified glass in the first injection channel portion 140 during injection cycles.

[0071] Figure 5This is an enlarged schematic cross-sectional view of the first (fixed) mold half 304, showing a heated runner bushing 110 having one or more heat insulation members 170, 174. In the illustrated embodiment, the heat insulation members include a first heat insulation member 170 disposed along a flange 126 between a countersunk hole 130 of the first mold half 304 and the bottom of a head portion 118 of the heated runner bushing 110. In this position, the first heat insulation member 170 is configured to insulate the heated runner bushing 110 from the first mold half 304. The heat insulation members may also include a second heat insulation member 174 disposed at the top of the head portion 118 of the heated runner bushing 110. In this position, the second heat insulation member 174 is configured to separate the heated runner bushing 110 from the nozzle 232 adjacent to the heated runner bushing 110 during an injection cycle. Figure 2 Heat insulation.

[0072] In one embodiment, one or more insulating members 170, 174 are configured in the shape of relatively thin gaskets, the inner and outer diameters of which are designed to provide sufficient contact surface area for their insulating function. In another embodiment, the insulating members 170, 174 are formed of a material configured to have sufficient compressive strength when positioned around the heated runner bushing 110 as described herein. The material of the insulating members 170, 174 is further configured to withstand degradation at temperatures up to about 500°C (or higher), which may correspond to the typical operating temperatures of the injection molding systems disclosed herein. Example materials that can be used for the insulating members 170, 174 are Mica M / Cogetherm M / Pamitherm® M supplied by Red Seal Electric Company. It should be understood that other materials may be used for the insulating members 170, 174 in other embodiments.

[0073] Refer again Figure 3AThe injection molding system 100 further includes one or more temperature sensors 162(a), 162(b) configured to measure the temperature of one or more portions of the heated runner bushing 110. The sensors may include a first sensor 162(a) configured to measure a first temperature of a portion of the heated runner bushing 110. The sensors may also include a second sensor 162(b) configured to measure a second temperature of a portion of the heated runner bushing 110. The sensors may include additional temperature sensors configured to measure multiple temperatures along corresponding portions of either or both of the first runner bushing portion 138 and the second runner bushing portion 142. In the illustrated embodiment, the first sensor 162(a) and the second sensor 162(b) are positioned along different portions of the second runner bushing portion 142. In an exemplary embodiment (not shown), the first sensor 162(a) is positioned along a portion of the first runner bushing portion 138 to measure its first temperature.

[0074] In embodiments, some of the methods, processes, actions, and / or steps described herein may be performed by controller 500. Controller 500 may include operational connections to various systems, devices, sensors, etc., associated with injection molding system 100. For example, one or more sensors 162(a), 162(b) may transmit temperatures measured by the sensors to controller 500 using signals (e.g., electrical signals, fiber optic signals, and / or wireless signals). Controller 500 may perform determinations, such as calculations, as described later in this disclosure, using signal data from one or more sensors 162(a), 162(b). Controller 500 may then generate one or more commands based on the determinations / calculations and transmit these commands to initiate, adjust, and / or stop actions associated with injection molding system 100. For example, one or more of the first heaters 150, 150a and the second heaters 154, 154a may be configured to receive one or more commands from controller 500 to initiate, adjust, and / or stop heating parameters, such as turning the heaters on or off and / or adjusting the heating rate of the heaters.

[0075] The controller 500 is configured to operate the injection molding system 100 to perform an injection molding cycle. In an embodiment, the controller 500 is configured to operate the injection molding system 100 to guide molten glass from the injection device 204 into the mold cavity 324 along (continuous) channels (e.g., including nozzle channel 236, runner channel 134, and runner channel 328). For example, refer to... Figure 2Once an injection volume of molten glass is established within cylinder 216, the controller can operate piston 220 to extend and discharge the injection volume of molten glass into nozzle channel 236. Molten glass is continuously guided through the channel until piston 220 is fully extended within cylinder 216, or until controller 500 stops its extension before piston 220 is fully extended.

[0076] In an embodiment, after the molten glass is guided along the channel and the molten glass fills the mold cavity 234, the controller 500 is configured to operate the injection molding system 100 to solidify the molten glass within the mold interior 316 of the mold 300, thereby (i) forming precision optical elements from the solidified glass in the mold cavity 234 and (ii) forming runner elements from the solidified glass in the runner channel 328. In an embodiment, solidifying the molten glass may include holding the mold 300 in a closed / locked position for a sustained solidification dwell time. During the solidification dwell time, the piston 220 may still be operated to apply a holding pressure to the molten glass within the mold 300.

[0077] In an embodiment, after the glass melt within the mold 300 has sufficiently solidified (i.e., the solidification dwell time has been reached), the controller 500 is configured to operate the injection molding system 100 to eject precision optical components and runner components from the mold 300. For example, the clamping system 400 may be actuated to move the second mold half 308 to the mold opening position, and one or more ejector pins of one or more of the first mold half 304 and the second mold half 308 may be actuated to eject the precision optical components and runner components from the mold 300.

[0078] In an embodiment, during any one or more of heating (e.g., heating chalcogenide glass particles to form a glass melt), guiding (e.g., guiding the glass melt along a channel), and solidification (e.g., solidifying the glass melt within the mold), the controller 500 is configured to operate the first heaters 150, 150a to heat the first runner channel portion 140 of the runner channel 134 adjacent to the runner channel 328, such that when the runner element is ejected from the mold 300, the solidified glass within the first runner channel portion 140 is configured to be completely detached from the first runner channel portion and ejected together with the runner element. As used herein, the phrase “completely detached” means that the solidified glass within the first runner channel portion 140 (i) does not crack or break when pulled out of the first runner channel portion 140 by the runner element, and (ii) leaves no residue (glass or other) within the first runner channel portion 140 when pulled out of the first runner channel portion 140 by the runner element.

[0079] In an embodiment, heating the first runner channel portion 140 further includes changing the heating rate of the first heater 150 such that the first runner bushing portion 138 has a first setpoint temperature simultaneously with the ejection of the precision optical element and the runner element. As used herein, the phrase "simultaneously with ejection" means that the first runner bushing portion 138 has the first setpoint temperature at the earliest moment when the precision optical element is ready to be ejected from the mold, such as at the moment when the solidification dwell time is reached after the glass melt is injected into the mold 300. In other words, the ejection of the precision optical element is not delayed, thus allowing additional time for the first runner bushing portion 138 to reach the first setpoint temperature. Instead, the output of the first heater 150 is adjusted (i.e., by increasing / decreasing or otherwise changing its heating rate) to ensure that the first runner bushing portion 138 has the first setpoint temperature simultaneously with ejection.

[0080] In an embodiment, during any one or more of heating (e.g., heating chalcogenide glass particles to form a glass melt), guiding (e.g., guiding the glass melt along a channel), and solidification (e.g., solidifying the glass melt within a mold), the controller 500 is configured to operate the second heaters 154, 154a to heat the second runner channel portion 144 of the runner channel 134 near the nozzle channel 236, such that the glass melt in the second runner channel portion 144 remains liquid. In an embodiment, heating the second runner channel portion 144 includes maintaining the second runner bushing portion 142 at a second setpoint temperature. In an embodiment, maintaining the second runner bushing portion 142 at the second setpoint temperature can be achieved by using a constant heating rate of the second heaters 154, 154a and / or cycling the second heaters between an on and off state as needed.

[0081] In an embodiment, the controller 500 is configured to implement a first routine to operate the first heaters 150, 150a. For example, the controller may be configured to: (i) receive a (measured) first temperature from a first sensor 162(a); (ii) compare the first temperature with a (predetermined) first setpoint temperature; and (iii) generate a first command based on the comparison. Thereafter, the first heaters 150, 150a are configured to receive the first command and change their heating rate such that, simultaneously with ejection, the first runner bushing portion 138 has the first setpoint temperature. As examples of the first routine, consider the following two cases.

[0082] In both cases, mold 300 is just filled with molten glass, and the solidification dwell time is approximately 10 seconds (e.g., the mold will remain in the clamped position for approximately 10 seconds to allow the molten glass therein to fully solidify before the molded part is ejected from the mold). In both cases, the (predetermined) first setpoint temperature of the first runner bushing portion 138 of the runner bushing 110 is approximately 290°C. In the first case, the first temperature at the first runner bushing portion 138 measured by the first sensor 162(a) is approximately 288°C. In the second case, the first temperature at the first runner bushing portion 138 measured by the first sensor 162(a) is approximately 286°C. Therefore, the first temperature in the second case deviates further from the first setpoint temperature compared to the first temperature in the first case. Since both schemes have the same amount of time (e.g., 10 seconds) to raise the measured first temperature of the first runner bushing portion 138 to the first setpoint temperature, the controller 500 needs to apply a higher heating rate to the first heater in the second case than the heating rate required for the first heater in the first case, so as to reach the first setpoint temperature in time before ejection.

[0083] In an embodiment, the controller 500 is configured to execute a second routine to operate the second heaters 154, 154a. For example, the controller may be configured to: (i) receive a (measured) second temperature from a second sensor 162(b); (ii) compare the second temperature with a (predetermined) second setpoint temperature; and (iii) generate a second command based on the comparison. Thereafter, the second heaters 154, 154a are configured to receive the second command and maintain the second runner bushing portion 142 at the second setpoint temperature, for example, by using a constant heating rate of the second heaters 154, 154a and / or by cycling the second heaters between an on and off state.

[0084] In this embodiment, the first setpoint temperature is configured to be greater than or equal to the second setpoint temperature. In this embodiment, the first setpoint temperature is at least 10°C higher than the second setpoint temperature, such as 11°C, 12°C, 13°C, 14°C, 15°C, 16°C, 17°C, 18°C, 19°C, 20°C or higher.

[0085] Chalcogenide glasses have a steep viscosity profile, meaning that even minute temperature changes can significantly affect their flowability. Specifically, during the solidification of the glass melt after filling the mold cavity 324, and just before opening the mold 300 to eject the molded part (e.g., a precision optical element), the temperature of the glass currently solidifying / solidifying in the first runner bushing portion 138 must be precisely controlled to ensure that such solidified glass is completely removed from the mold 300 during the ejection of the precision optical element and runner element. Due to the steep viscosity profile of chalcogenide glasses, existing heated runner bushings may not provide sufficient temperature control resolution. The heated runner bushing disclosed herein, together with the injection molding system 100 and operating method disclosed herein, enables the injection molding of precision optical elements with chalcogenide glasses, which would otherwise be impossible.

[0086] The term "controller" should not be construed as limiting the embodiments disclosed herein to any particular device type or system. In embodiments, the controller includes a computer system. The computer system may be a laptop computer, a desktop computer, or a mainframe computer. The computer system may include a graphical user interface (GUI) so that a user can interact with the computer system. The computer system may also include a computer processor (e.g., a microprocessor, a microcontroller, a digital signal processor, or a general-purpose computer) for performing any of the methods and processes described above.

[0087] The computer system may also include memory, such as semiconductor memory (e.g., RAM, ROM, PROM, EEPROM, or flash programmable RAM), magnetic memory (e.g., floppy disk or fixed disk), optical memory (e.g., CD-ROM), PC card (e.g., PCMCIA card), or other memory. For example, this memory may be used to store measured temperatures of different portions of the heated injection molding bushing 110 and predetermined setpoint temperatures of these different portions.

[0088] Some of the methods and processes described above can be implemented as computer program logic for a computer processor. Computer program logic can be embodied in various forms, including source code or computer-executable form. Source code can include a series of computer program instructions in various programming languages ​​(e.g., object code, assembly language, or high-level languages ​​such as C, C++, or JAVA). Such computer instructions can be stored in a non-transitory computer-readable medium (e.g., memory) and executed by a computer processor. Computer instructions can be distributed in any form as a removable storage medium having accompanying printed or electronic documentation (e.g., compressed software packages), pre-loaded with a computer system (e.g., on system ROM or a fixed disk), or distributed from a server or electronic bulletin board via a communication system (e.g., the Internet or the World Wide Web).

[0089] Alternatively or concurrently, the controller may include discrete electronic components coupled to a printed circuit board, an integrated circuit system (e.g., an application-specific integrated circuit (ASIC)), and / or a programmable logic device (e.g., a field-programmable gate array (FPGA)). Any of the methods and processes described above can be implemented using such logic devices.

[0090] While this disclosure has been illustrated and described in detail in the accompanying drawings and the foregoing description, the drawings and the foregoing description should be considered illustrative rather than restrictive. It should be understood that only preferred embodiments are presented, and protection is intended for all changes, modifications, and further applications within the spirit of this disclosure.

Claims

1. A method for forming a precision optical element by injection molding, the method comprising: Particles of chalcogenide glass are heated in an injection apparatus to form a glass melt, wherein 10% of the chalcogenide glass... 4.0 P temperature is 500°C or lower and in the range of 1,000 sec -1 Up to 10,000 sec -1 It exhibits resistance to crystallization at shear rates; The molten glass is guided along a channel from the injection device into a mold cavity that negatively defines the precision optical element. The channel includes: A nozzle channel through which the molten glass is configured to be guided from the injection device, the nozzle channel being defined by the injection device. A runner channel through which the molten glass is configured to be guided into the mold cavity, the runner channel being defined by the mold interior. The molten glass is configured to be guided from the nozzle channel to the flow channel through the sprue channel, the sprue channel being defined by a heated sprue bushing extending through the mold from inside the mold to outside the mold spaced apart from the mold interior; The glass melt is solidified inside the mold to (i) form the precision optical element from the solidified glass in the mold cavity, and (ii) form a flow channel element from the solidified glass in the flow channel. The precision optical element and the flow channel element are ejected from the mold; as well as The first sprue channel portion adjacent to the runner channel is heated by a first heater, such that when the runner element is ejected from the mold, the solidified glass within the first sprue channel portion is configured to completely detach from the first sprue channel portion and be ejected together with the runner element.

2. The method of claim 1, wherein the heated runner bushing has a first runner bushing portion defining the first runner channel portion, and wherein heating the first runner channel portion comprises changing the heating rate of the first heater such that, at the same time as the ejection, the first runner bushing portion has a first setpoint temperature.

3. The method of claim 2, further comprising heating a second injection channel portion of the injection channel adjacent to the nozzle channel with a second heater, such that the glass melt in the second injection channel portion remains liquid.

4. The method of claim 3, wherein the injection channel includes a narrowing transition portion separating the first injection channel portion from the second injection channel portion.

5. The method of claim 4, wherein the heated runner bushing has a second runner bushing portion defining the second runner channel portion, and wherein heating the second runner channel portion comprises maintaining the second runner bushing portion at a second set point temperature.

6. The method according to claim 5, wherein the first setpoint temperature is greater than or equal to the second setpoint temperature.

7. The method according to claim 5, wherein the first setpoint temperature is at least 10°C higher than the second setpoint temperature.

8. The method according to any one of claims 1 to 7, wherein the mold comprises (i) a first half-mold fixed in position relative to the injection device and (ii) a second half-mold configured to translate relative to the first half-mold, the heated runner bushing being disposed in the first half-mold.

9. The method of claim 8, wherein the second half mold is configured to translate between (i) a mold-locking position during the guiding and solidification and (ii) a mold-opening position during the ejection, wherein in the mold-locking position the second half mold is pressed against the first half mold, and in the mold-opening position the second half mold is spaced apart from the first half mold.

10. The method according to any one of claims 1 to 9, wherein the injection channel is configured to be continuous along its entire length between the outside of the mold and the inside of the mold.

11. The method according to any one of claims 1 to 10, further comprising: Prior to the guiding process, an injection volume of the glass melt is established in the injection device under a first pressure; and After the injection volume is established, a second pressure greater than the first pressure is applied to the injection volume in the injection device for a first duration to degas the glass melt.

12. An injection molding system comprising: An injection apparatus configured to heat chalcogenide glass particles to form a glass melt, wherein 10 of the chalcogenide glass 4.0 P temperature is 500°C or lower and in the range of 1,000 sec -1 Up to 10,000 sec -1 The glass melt exhibits resistance to crystallization at shear rates of [specific values], and the injection device includes a nozzle that defines a nozzle channel, the glass melt being configured to be guided from the injection device through the nozzle channel. A mold having an exterior and an interior spaced apart from the exterior, the interior defining a mold cavity and a runner channel, the glass melt being configured to be guided into the mold cavity through the runner channel, the mold cavity being configured to negatively define a precision optical element; A heated runner bushing extends through the mold from the outside of the mold to the inside of the mold, the heated runner bushing defining a runner channel through which the glass melt is guided from the nozzle channel to the flow channel; Controller, the controller being configured to operate the injection molding system to: The molten glass is guided from the injection device along the nozzle channel, the runner channel, and the flow channel into the mold cavity. The glass melt is solidified inside the mold to (i) form the precision optical element from the solidified glass in the mold cavity, and (ii) form a flow channel element from the solidified glass in the flow channel. The precision optical element and the flow channel element are ejected from the mold; as well as A first heater is configured to heat a first runner channel portion adjacent to the runner channel, such that when the runner element is ejected from the mold, the solidified glass within the first runner channel portion is configured to completely detach from the first runner channel portion and be ejected together with the runner element.

13. The injection molding system according to claim 12, wherein: The heated injection port bushing has a first injection port bushing portion that defines the first injection port channel portion. The injection system further includes a first sensor configured to detect a first temperature at the first injection channel bushing portion. The controller is configured to: (i) receive the first temperature from the first sensor, (ii) compare the first temperature with a first setpoint temperature, and (iii) generate a first command based on the comparison. The first heater is configured to receive the first command and change the heating rate of the first heater such that, at the same time as the ejection, the first injection duct bushing portion has the first set point temperature.

14. The injection molding system of claim 13, further comprising a second heater configured to heat a second runner portion of the runner channel adjacent to the nozzle channel, such that the glass melt in the second runner channel portion remains liquid.

15. The injection molding system of claim 14, wherein the runner includes a narrowing transition portion separating the first runner portion from the second runner portion.

16. The injection molding system according to claim 15, wherein: The heated runner bushing has a second runner bushing portion that defines the second runner channel portion. The injection system also includes a second sensor configured to detect a second temperature at the second injection channel bushing portion. The controller is configured to: (i) receive the second temperature from the second sensor, (ii) compare the second temperature with a second setpoint temperature, and (iii) generate a second command based on the comparison. The second heater is configured to receive the second command and maintain the second injection duct bushing portion at the second set point temperature.

17. The injection molding system of claim 16, wherein the first setpoint temperature is greater than or equal to the second setpoint temperature.

18. The injection molding system of claim 16, wherein the first setpoint temperature is at least 10°C higher than the second setpoint temperature.

19. The injection molding system according to any one of claims 12 to 18, wherein the mold comprises (i) a first half mold fixed in position relative to the injection device and (ii) a second half mold configured to translate relative to the first half mold, the heated runner bushing being disposed in the first half mold.

20. The injection molding system of claim 19, wherein the second half-mold is configured to translate between (i) a locked position when the glass melt is guided from the injection device and solidified within the mold and (ii) an open position when the precision optical element and the runner element are ejected from the mold, wherein in the locked position the second half-mold is pressed against the first half-mold, and in the open position the second half-mold is spaced apart from the first half-mold.

21. The injection molding system according to any one of claims 12 to 20, wherein the runner channel is configured to be continuous along its entire length between the outside of the mold and the inside of the mold.

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