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Insights of 3D Printing Technology with Its Types
Published in Harish Kumar Banga, Rajesh Kumar, Parveen Kalra, Rajendra M. Belokar, Additive Manufacturing with Medical Applications, 2023
Ranbir Singh Rooprai, Jaswinder Singh
Digital light processing (DLP), also called a digital micromirror device (DMD), uses aluminium-based mirrors for reflecting the light to make pictures. It refers to the DLP chip. DLP is a 3D-printing procedure in which photopolymer resin is fixed using a projector. DLP technology is similar to the stereolithography (SLA) technique since it interacts through a 3D-printing system with photopolymers. The only difference in DLP is that a protected light is used instead of an ultraviolet laser for the cure of photopolymers. The items are formed in the same manner as SLA. It is taken out from the object so the resin creates space for the untreated part. Then layer-by-layer forming from the base of the container into the tank with a fix on top of the next layer happens. DLP was invented by Larry Hornbeck in 1987 [11]. DLP accepts analogue or digital signals and converts the picture into video, mostly used in cell phones and projectors. It uses a more conventional lamp, which is much simpler and more powerful than SLA and has a crystal show shape. It offers better surface finishing and is better than other methods [12,13]. Figures 2.2 and 2.3 represent a view of the working of DLP. Liquid plastic resin is used as we know in DLP printers. It is hardened and easier to operate than other forms of resin. Due to the high hardness, strength and chemical stability, ceramic materials are used in various industries. At a jerk speed, DLP prints highly compatible products [14,15]. The harder content is rendered easily and quickly by this sort of printer sheet. When one layer is done, it is moved and the next layer begins.
The Home Cinema
Published in Lars-Ingemar Lundström, Understanding Digital Television, 2012
The competing technology is DLP, digital light processing and consists of a matrix with hundreds of thousands small mirrors whose orientation can be affected by electrical signals in the same way as the pixels in plasmas or LCDs. The micro-mirror chip is generally called DMD, for digital micro-mirror device. By pointing the mirrors in the right direction, the light from that pixel will be exposed on the projection screen. It is very similar to when you are traveling by car and suddenly get a reflection of the sun in a window that happens to be in the right angle to reflect the light straight towards you. The advantage in the DLP technology is that the contrast ratio in the picture will be much better than for LCD. The risk for the device to be over-heated by the light source is also much lower than in LCDs, since the light is reflected. This also makes it possible to use very bright light sources. In most cases only one DLP is used to produce all three colors. The three basic color pictures are produced in sequence by letting the light pass a rotating wheel with filters corresponding to the three basic colors (see Figure 11.7).
More on Pictures
Published in Peter Hodges, An Introduction to Video and Audio Measurement, 2013
Projectors fall into two types: LCD and DLP. The former functions similarly to a flat panel screen but uses three LCD filters, red, green and blue, the light from the lamp being spilt by dichroic mirrors or prisms. The DLP (digital light processing) projector uses DMD (digital micromirror device), a panel of pixel-size mirrors that move under the influence of the signal, to throw light into, or away from, the projection lens, so creating light and dark. There are three-colour DMDs, red, green and blue, and single DMD using a colour wheel that is mainly confined to lower-power versions.
Driving Towards the Future: Exploring Human-Centered Design and Experiment of Glazing Projection Display Systems for Autonomous Vehicles
Published in International Journal of Human–Computer Interaction, 2023
Yancong Zhu, Yunke Geng, Ruonan Huang, Xiaonan Zhang, Lu Wang, Wei Liu
The advancement of automotive glazing projection display technology is primarily attributed to hardware technology development (Lampert, 2003; Sadek & Mahrous, 2018). In projection technology research, Digital Light Processing (DLP) technology is employed as the projection source (Kadry et al., 2019). Texas Instruments Digital Micromirror Device (DMD) is the basis for DLP technology, which allows for the digital visual display of information (Yang et al., 2021). DMD rapidly switches pixels and blends the three RGB primary colors to produce a vivid and realistic image. DLP technology has a significant performance advantage since its switching characteristics remain stable despite changes in temperature, which maintains image quality and color reproduction. Sunlight backflow is prevented, and projection clarity is enhanced through temperature control. The placement of the DLP projector determines front or rear projection, and information can be displayed on the windshield inside and outside the vehicle. Unlike W-HUD, DLP projection produces an authentic image visible from any position within the vehicle.
Use of additive manufacturing for the fabrication of cellular and lattice materials: a review
Published in Materials and Manufacturing Processes, 2021
Esmeralda Uribe-Lam, Cecilia D. Treviño-Quintanilla, Enrique Cuan-Urquizo, Oscar Olvera-Silva
The digital light processing (DLP) technique uses a projection mechanism that screens a single image which represents the 2D version of each layer, producing small square volumetric pixels (voxels).[76] Luxner and coworkers [77] used digital light processing and selective laser sintering (SLS) to produce different cellular materials simple cubic (SC) (Fig. 5c), body-centered cubic (BCC) (Fig. 5d) and Gibson – Ashby (GA) (Fig. 5e). They compared their relative density, stiffness, and directional dependence on their apparent Young’s moduli obtained both experimentally and computationally. The digital light processing (DLP) lattice structures were created with a 40 mm pixel resolution, considered as high resolution, and a 0.2 mm wall thickness; smaller when compared with the 0.4 mm wall thickness of selective laser sintering. The fabrication times were very similar for all the structures in this study. The main advantages of digital light processing in comparison with selective laser sintering are the fabrication time and no-support requirement for the manufacturing of lattice materials and porous structures. Digital light processing is an ideal alternative to produce lightweight ceramic structures as triply periodic minimal surfaces. The parts fabricated by digital light processing and a sintering process show homogeneity at the grain size, but the organic components of the resins may cause the formation of porous structures in the material.[78]
Recycling strategies for vitrimers
Published in International Journal of Smart and Nano Materials, 2022
Haochuan Zhang, Jingjing Cui, Guang Hu, Biao Zhang
In 2018, Zhang et al. [52] transferred the concept to photo-curable resins printable by Digital Light Processing (DLP). Compared to DIW, DLP offers several advantages as it enables the fabrication of 3D objects with high resolution and surface quality and comparably high throughput rates. They developed the first 3D printed reprocessable thermosets (3DPRTs) by combining vitrimers with DLP 3D printing technology (Figure 9(a)). They prepared a photosensitive resin precursor with 2-hydroxy-3-phenoxypropyl acrylate monomer, bisphenol A glycerolate (1 glycerol/phenol) diacrylate as a crosslinker, and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide as a photoinitiator[115]. During the DLP 3D printing process, the double bonds of the acrylate open and form a permanent covalent cross-linked network with the cross-linker, allowing the liquid to cure, layer by layer, eventually forming a three-dimensional structure. By heating the 3D structure to a higher temperature, the ester exchange reaction between the ester and the hydroxyl group in the polymerized network is achieved in molding, repair or recycling. This material allows users to reform a printed 3D structure into a new arbitrary shape, repair a broken part by simply 3D printing new material on the damaged site (Figure 9(b)), and recycle unwanted printed parts (Figure 9(c,d)) so the material can be reused for other applications [88,89,114,116,117]. The recycling of vitrimer was achieved using the above methods, but repeated 3D printing could not be achieved. Gao et al. [118] demonstrated a new strategy for developing a kind of mechanically robust and reprocessable 3D printing thermosets by combining hydrogen bonds and exchangeable β-hydroxyl esters into acrylate vitrimers. To realize this purpose, diacrylate prepolymer containing β-hydroxyl esters was first synthesized from glycidyl methacrylate and suberic acid. Then, the resin formulations for 3D printing comprising the synthesized diacrylate prepolymer together with acrylamide generate exchanged β-hydroxyl ester and pendent amide in cross-linked networks. Here, hydrogen bonds resulting from the amide group as sacrificial bonds dissipate vast mechanical energy under an external load. The network rearrangement of cross-linked vitrimers can be achieved through the dynamic ester exchange reactions with the gradual disappearance of hydrogen bonds at elevated temperatures, imparting reprocessability into the printed structures. The network rearrangement of cross-linked vitrimers can be achieved through the dynamic ester exchange reactions with the gradual disappearance of hydrogen bonds at elevated temperatures, imparting reprocessability into the printed structures. Various photo-3D printing or UV irradiation shapes were successfully produced, and these shapes dissolved in EG could be remolded again. The recycling of vitrimer was achieved using the above methods, but repeated 3D printing was still an issue.