Luxexcel, a company dedicated to 3D printing of optical lenses, announced that it is ready for the next growth of smart glasses, offering lens production solutions for the smart glasses market through lens-specific 3D printing equipment, materials, software and expertise in optics.

Luxexcel's mass production 3D printing solution for smart glasses will improve on these existing problems by creating lenses embedded with smart features and will meet the need to produce customized smart glasses lenses for everyday eyeglass wearers, allowing These wearers will no longer need to wear additional vision correction glasses when using smart glasses.

In this issue, 3D Science Valley will analyze Luxexcel's lens 3D printing technology and the process of manufacturing functionally integrated smart lenses.

Luxexcel's 3D printed lens with integrated waveguide and LCD screen. Source: Luxexcel

Lightweight and comfortable smart glasses

Luxexcel recently announced that manufacturers of eyewear products can use Luxexcel's proven mass production solution to combine prescription formulations with smart technology to create regular-looking lenses with advanced smart features while meeting the vision correction needs of their customers.

The mass production solution Luxexcel refers to is a solution based on material jetting 3D printing technology that includes proprietary hardware, materials and software. 3D printing solutions can 3D print on substrate materials such as plastic and glass, and can also meet customer air gap requirements.

With this process, smart devices like waveguides, holographic films and LCD screens can be embedded in the lens manufacturing process, becoming a lens with integrated smart features. The lenses can also be produced according to the user's personalized lens prescription recipe. Thanks to the 3D printing technology, which does not require molds, a wide range of lenses with different prescriptions can be manufactured in a single print, which is the basis for the production of smart lenses on a customized scale.

Optimized for the specific requirements of optical components

According to 3D Science Valley's market research, Luxexcel has filed a patent in the field of embedded 3D printing of smart components. According to Luxexcel , this method of assembling optical components is easy to automate and use for mass production without compromising the precision required for the production of optical components. With the advantages of 3D printing technology, this technique enables rapid on-demand manufacturing of optical components.

Block Smart Lens Manufacturing Process

Luxexcel's patented technology consists of the following steps: placing the substrate material on the substrate and loading it into the printing device; a first printing step: depositing the print material on the first surface of the substrate, creating an intermediate first pre-structure; a second printing step: depositing droplets of the print material on the second surface of the substrate in sequence; in a rearrangement step between the first and second steps, forming an intermediate second pre-structure, rotating the first pre-structure and arranging the first pre-structure on a support structure, the support structure comprising a carrier sub-structure with an extension of the substrate material resting at least partially on the carrier sub-structure.

In the above process, the optical part 3D printing material is printed on the substrate material in a double-sided printing manner. Usually due to shrinkage of the layer material, shrinkage distortion of the 3D printed part is inevitable during material curing. Common countermeasure strategies are to compensate for this shrinkage effect by feedforward or feedback control, i.e., pre-compensation for shrinkage in the design of the 3D structure, or dynamic compensation of the object shape by adjusting the printing process based on dynamic real-time monitoring. However, these countermeasures do not eliminate the shrinkage effect, but compensate for the resulting deformation.

Luxexcel_2 Source: US 20190009481

Luxexcel's technique for 3D printing of optical parts on a substrate material, however, prevents shrinkage without resorting to compensatory measures. The 3D structure built on the substrate material retains both its internal layered structure and its intended final shape. This technique is particularly important for the manufacture of parts that are negatively affected by internal layer deformation, which is the case of optical lenses and parts with embedded components that require a fixed geometric position.

In addition, the substrate provides extensions, including fixed extensions, anti-capillary extensions, and/or processing extensions. Fixed extensions serve to fix the pre-structure during the printing process. The processing extensions allow for easy handling of the optical components during the printing process, preventing the actual printed structure from deteriorating due to contact. The anti-capillary action extension serves to prevent capillary action from dragging a portion of the pre-structure into the gap between the first pre-structure and the support structure during and after the rearrangement step. In this way, undesired deformation of the pre-structure due to capillary effects is avoided and the bonding of the first and/or second pre-structure to the support structure is prevented.

In summary, it can be said that this is a technique for printing optical components with the desired shape, free from deformation, avoiding the deformation of the pre-structure due to the capillary effect and preventing the bonding of the first and/or second pre-structure to the support structure. This is particularly advantageous for the manufacture of optical components.

The support structures in the print include deformation control substructures, which serve to control the deformation of the pre-structures. On the one hand, the deformation control substructures protect the pre-structure from sagging, in particular due to gravity, but also from deformation due to shrinkage of the printed material and from deformation due to thermal effects such as thermal expansion. On the other hand, the deformation control substructure can be used to induce the desired deformation in the pre-structure, e.g., the first pre-structure can be slowly inflated to obtain a bent-moon lens by printing on one side.

block Particularly smooth surfaces

The 3D printing technique used to achieve the manufacturing of the parts described above is a material jetting technique in which the print heads deposit droplets of ink side by side and one after the other, gradually achieving the printing of a three-dimensional structure, with multiple droplets being simultaneously ejected by multiple nozzles of the print head in each deposition step.

In common 3D printing technologies on the market, the deposited droplets are at least partially cured after each deposition step in the curing step. Luxexcel's 3D printing technology allows for a time lapse between the deposition of droplets and their curing, allowing the droplets to flow under the influence of gravity in a direction tangential to the surface of the layer just printed, resulting in a particularly smooth surface, which is particularly important for optical lenses The smoothness is particularly important for optical lenses.

3D Science Valley Review

Unlike many companies that offer 3D printing-additive manufacturing technologies for a wide range of applications, Luxexcel has been focused on the additive manufacturing of optical lenses since its inception. They have partnered with innovative eyewear manufacturers, smart device makers or doctors to explore the application of 3D printing technology in optical lens manufacturing.

Eliminating the need for large inventories, complex supply chains, greater freedom in product design, and enabling mass production of customized lenses are what Luxexcel believes 3D printing technology brings to the optical lens manufacturing industry in a special way. 3D Science Valley will continue to track the new opportunities this technology brings to the eyewear manufacturing sector.

Source: 3D Science Valley