#DMD-matrices

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DLP projector working

As known, DLP (Digital Light Processing) technology was developed in 1987 by a Texas Instruments Larry Hornbeck engineer based on a DMD chip. After 10 years, Digital Projection Ltd introduced the first active DLP projector. In 1998, Texas Instruments and Digital Projection Ltd received an Emmy Award for technical achievement. Today, DLP projectors successfully compete with 3LCD and LCoS models. Of course, the type of projector affects its spec and, accordingly, its choice. As a rule, most modern DLP projectors use only one semiconductor DMD (Digital Micromirror Device) chip, which forms an image using a huge number of micromirrors. This chip contains an array of micromirrors with system of their position control. For example, Full HD DMD chip contains 1920 * 1080 = 2,073,600 micromirrors. Electric signal practically instantly turns each mirror to one of two fixed positions, providing reflection of light either through the lens or onto a heat sink. Thus, each mirror reflects the light of the lamp either onto the screen or onto a heat sink of the projector, forming, respectively, a white or black dot on the screen. Multiple switching from black to white provides shades of gray on the screen.

Operation principle

Unfortunately, a 1-chip projector at a time passes only one component of a color image to the screen. A rotating wheel with color filters (color wheel) divides white light into individual colors. The color wheel is always located next to the light source. The first models rotated the color wheel at up to 3,600 rpm. But it was not enough to eliminate the rainbow effect, when the object contour acquires multicolored artifacts. Increasing its rotational speed reduces this effect. In addition, the color wheel reduces brightness. Texas Instruments has created Brilliant Color technology with a six-segment RGBRGB disk and an additional. Six-segment disk reduces the time for changing colors by half. A transparent segment increases the luminous flux, but reduces the number of gradations due to the imbalance between the brightness of black and white and color images. Too high brightness of the black and white component worsens other colors, making them darker and faded. In the future, companies experimented with the addition of intermediate colors and the area of the transparent segment. Today, manufacturers use different color configurations. Modern 1-chip DLP projectors use mainly the 6-primary colors, including Red, Blue, Green, Cyan, Magenta and Yellow. The operation principle with mirrors provides deep black and, accordingly, high contrast. But switching the mirrors is sometimes accompanied by a decrease in the number of colors gradations, reducing the smoothness of color transitions.

2-chip and 3-chip DLP projectors

Companies also tried to develop a 2-chip DLP projector. Their color wheel divides light into red-green and red-blue colors. The prism system extracts the red component and sends it to one of the micro-mirror arrays. The green and blue components are alternately projected onto another chip. Further, two DMD-matrices modulate the corresponding rays, constantly projecting a red component on the screen. This circuit compensates for the insufficient intensity of the corresponding part of the lamp's emission spectrum. But it did not solve the problem of the rainbow effect and did not receive wide distribution. As a result, companies have developed a 3-chip design. This projector divides the luminous flux of the lamp into three components using special prisms. Then, each beam is directed to the corresponding DMD-chip, modulated and returned to the prism, which combines it with other color components. Finally, a prism sends a full-color image to the screen through the lens. The design of the 3-chip DLP projector provides very low response time, excellent contrast and high brightness. Using the reflection of the light flux virtually eliminates the loss of brightness, in contrast to the 3LCD projectors that work on light pass. Accordingly, less powerful lamps require a less powerful cooling system with less noise. But most modern DLP models use semiconductor light sources (LEDs or LED lasers), which do not require cooling at all. Moreover, the characteristics of the DMD-chip practically do not degrade over time. This video demonstrates the operation principle of TI DLP technology. Read the full article

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Abaqus paraview

#Abaqus paraview manual

#Abaqus paraview code

Especially, it handles mass data with difficulties, such as the extremely slow refreshing, limited functionalities and unexpected crash of software. Verification test suite can be seen below.Abaqus? is one of the most popular commercial finite element analysis(FEA) software, but the visualization function of post-processing module-Abaqus/CAE is relatively weak.

Usage by postProcess utility is not available.Ī set of plots showing cross-sections of mode fields from a two-dimensional.

Matrices are not supported due to the prohibitive computational costs.

Restart is currently not supported since intermediate writing of STDMD.

Would be cases whereat oddities might be encountered.

DMD is an active research area at the time of writing therefore, there.

This STDMD release is the beta release therefore, small-to-mediumĬhanges in input/output interfaces and internal structures should be.

Three mode sorting algorithms, and various filtering entries are.

Data compression by an orthonormal basis compression is possible.

=Scalar/Vector/SphericalTensor/SymmTensor/Tensor,

Templated input for which Field can be input.

Tall-skinny QR decomposition (except the eigendecomposition solver)

Parallel including the classical Gram-Schmidt procedure, and direct.

Method capabilities alongside economised and feasible memory and CPU usage,īy allowing incremental updates and data compression on orthonormal (2017), and Hemati et al.Īmong other DMD variants, STDMD is presumed to provide the general DMD Streaming Total Dynamic Mode Decomposition (STDMD) based on anĪlgorithm developed by Kiewat (2019), Hemati et al. This release includes a new DMD variant as a function object called An elegant and useful introduction to DMD theory is Interpretable, tractable, or even reproducible without computing the complete set modeįrequency and decay rate, so that dynamic features of the given flow may become Underlying physics, dimensionality reduction method that can be used to revealĪnd quantify dominant spatiotemporal-coherent structures from a given flow (orĭataset) in the form of modes, and associated mode parameters, e.g. New dynamic mode decomposition (DMD) function objectĭynamic Mode Decomposition (DMD) is a data-driven, i.e.

#Abaqus paraview code

Source code $FOAM_SRC/functionObjects/field/interfaceHeight Tutorial $FOAM_TUTORIALS/verificationAndValidation/interCondensatingEvaporatingFoam/stefanProblem Attribution The base of the interfaceHeight function object has been By default the heightĬalculation is set to be aligned with the gravity vector, but the optional directionĮntry can be used to set a different direction. The initial code has been extended to include an option to change the defaultĭirection from which the interface height is calculated. It uses an integralĪpproach, meaning that if multiple interfaces exist above or below a location an Point on the interface from which these heights are computed. For each location, the vertical distance of the interfaceĪbove both the location and the lowest boundary are written, complete with the The interfaceHeight object reports the height of the interface above a set of This function object has been ported from the repository. $FOAM_SRC/src/surfMesh/surfaceFormats/abaqus Surfaces in Abaqus format will be made available in future releases. Handling of surface extraction from solid elements and writing sampled SurfaceMeshConvert -read-format abaqus file.ext1 -write-format nastran file.ext2 ParaView, cellZones can be extracted from the Ensight format via the filter The figure below, where the various cell zones are highlighted in different colors. After running foamToEnsight, users can visualise the case as shown in The improved cellZones functionality can be tested on using tutorial case withĬellZones.

#Abaqus paraview manual

The full list of options can be found in the online manual and/or in the Suppress conversion of pointFields, disable -nodeValues Suppress removal of existing EnSight output directory Starting index for consecutive number of Ensight data/files. Specify single or multiple cellZones to writeĮxclude single or multiple patches (name or regex) from writing Individual parts for cellZones, unzoned cells ( internalMesh) and patches

[verymerynice]

New Post has been published on Top Auto Blog

New Post has been published on http://topauto.site/mercedes-will-be-able-to-draw-light-on-the-pavement/

Mercedes will be able to draw light on the pavement

Daimler presented a promising smart lights Digital Light, which are based on technology microthermal. Itself led optics, computer controlled, used for several years: luminous flux is formed dozens of tiny LEDs, and the computer may repay any sector, so as not to dazzle the driver of the oncoming or passing cars. The most advanced are the headlights of the new E-class with a matrix of 84 LEDs.

Possible scenarios of use of the headlamp microcirculate: tips navigation…

…overall tips when braking…

…and markers the width of the vehicle

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And in the perspective of Farah Digital Light emitted by the led flux is refracted with a special chip that has more than a million microthermal. That is, the number of elements from which a luminous flux exceeds two million! It is close to the resolution of modern computer monitors, which not only perfectly illuminate the road, but even “draw” with light tips to the driver directly on the pavement: for example, the arrow with the direction of movement at the crossroads, the markers of the width of the car when driving in narrow places or road markings where it has worn off.

This — LED-matrix serial Mercedes E-class with 84 LEDs (3 rows of LEDs is clearly visible in the center)

Similar developments have competitors from Audi, but their implementation in serial production is hampered by the high cost of DMD chips. So in the framework of the project Digital Light Daimler is developing an alternative and more simple light system. Created it for a LED matrix with 1024 LEDs. Each headlight is supposed to install four such matrices, that is, a light image will be a total of 8192 pixels.

In the center of the Board — chip microcirculate

And it looks promising LED matrix with 1024 LEDs

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LG HF80JA Full HD laser smart home theater projector

As known, the LG HF80JA was first introduced at CES 2107. This model became the first compact laser Full HD home theaters projector. It weighs only 4,6 lbs and has an unconventional vertical design.

Of course, this model can be positioned as a conceptually new projector. As known, the semiconductor light sources (LED and laser LEDs) actively displace lamps as a light source for projectors. Of course, the huge service life provides significant advantages to these models. In particular, many companies confidently promise 20,000-30,000 hrs. Unfortunately, LED projectors provide a too pale image due to low brightness. Laser models are too expensive (especially green laser LEDs), but they provide much more power. Some years ago, manufacturers were able to offer quite bright LED projectors (1000 ANSI lm). But the lack of Full HD matrices has become a new obstacle. Then they suddenly appeared at LG. Since that moment, the LED projector segment began to develop rapidly. LG PF1000U (1000 lm, 1920x1080) and PF1500G (1500 lm, 1920x1080) models have become its leaders.

LG HF80JA

This DLP model uses a single DMD chip and a laser phosphor, which provides 2000 ANSI Lm and has 20000 hour service life. Its cost is comparable to the price of lamps for projectors. Engineers placed it in a device worth up to $ 1,500, whose weight does not exceed 4.6 lbs. But the small weight is due to the use of an external power source. Of course, an additional block complicates the design. On the other hand, increasing the distance between it and the video path is optimal from the point of view of heat dissipation and electromagnetic interference. As a result, the HF80JS becam the lightest Full HD laser projector in this brightness segment. Moreover, the projector uses a webOS platform for Internet TV and access to streaming services. Additionally, HF80JA uses popular Magic Remote Control with a gyro, which operates as a computer mouse.

The marker moves on the screen in accordance with the hand movement without buttons. The innovative LG ProBeam Bluetooth Sound Out system provides wirelessly stream sound directly from the HF80JA projector to a Bluetooth compatible sound system, including like home audio speakers, headphones or portable speakers.

But, of course, Bluetooth-enabled speakers sold separately. In addition, the ProBeam function uses the Miracast standard for projecting content on a large demo screen. Digital Auto Keystone Correction (vertical) automatically detects and corrects any screen image distortion. Four Corner Keystone is designed to manually fine tune the picture positioning.

As a result, the system provides the perfect image.

Features

The image quality corresponds to the most HDTVs and low-cost home theater projectors. Unfortunately, the LG HF80JA does not support 4K, HDR and 3D. The settings menu has seven customizable, predefined color modes, including Vivid, Standard, Cinema, Sports, Game, Expert (Bright Room), and Expert (Dark Room). Picture has a slight green bias, which traditionally decreases in less bright modes. However, the projector provides fairly accurate color rendering even in bright Vivid. But to be honest, it can be detected only when compared with the image of a calibrated projector. As known, color fidelity depends on color temperature. Respectively, changing color temperature from medium to cool increases its accuracy. Moreover, two Expert modes offer more advanced picture controls, including Color Gamut, Gamma and ability to adjust Saturation, Tint, and Luminance separately for red, green, blue, cyan, yellow, and magenta. As known, the human eye perceives the colors created by lazar as brighter. Therefore, some companies often specify in the spec values given the "equivalent perception". Unfortunately, measured input lag reaches 67 ms in all modes. The projector provides a contrast ratio of 150,000: 1, but the black depth corresponds only to the average level. Model uses 1.10:1 zoom lens. Throw ratio of 1.40:1 - 1.54:1 provides Image Size of 69 - 305 cm with Throw Distance of 0.9 - 3.7 m. For example, the projector can form a projections of 100"@ 8,2 ft or 79"@6.6ft.

PROS & CONS

PROS - cinematic viewing with Full HD resolution (1920 x 1080);

- very high brightness for laser projectors; - Digital Auto Keystone Correction (vertical) and Four Corner Keystone; - long service life (laser, 20 000 hrs); - wirelessly stream sound directly from the HF80JA projector to a Bluetooth compatible sound system (ProBeam Bluetooth Sound Out system); - built-in speakers (2 x 3 W, stereo); - wireless support for Miracast, WiDi, and DLNA; - wireless support for connection to iOS/Android devices with the TV Plus app; - Keyboard/mouse/GamePad connection via USB; - USB playback of DivX, MP3, and select photo file types; - Quick On (10 seconds) / Quick Off (2 seconds); - very light weight. CONS - no WCG support; - no lens shift; - remote requires very accurate signal direction. Projector ignores commands even when offset to few degrees left or right; - no VGA connector; - slow menu response; - no support for 4K, HDR and 3D; - max screen size is only 120"; - weak rainbow effect. This video shows the LG HF80JA projector. Read the full article

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Epson Home Cinema 5050UB (EH-TW9400) vs Epson 5040UB (EH-TW9300)

As known, in June 21, 2016, Epson introduced 3LCD 5040UB/5040UBe (EH-TW9300) and Pro Cinema 4040 projectors with 4K UHD and HDR support for under $3,000. Unlike UB models, UBe projectors have module for support wireless HDMI technology based on the well-regarded WirelessHD standard. Of course, they are more expensive about $ 300. These models used wobulation (e-shift, pixel-shifting or 4K- Enhancement) technology for increasing the resolution to 3840 x 2160. But, this resolution differs from Native 4K (4096 x 2160) and True 4K. As known, True 4K with Two-Phase or Four-Phase Pixel Shifting use 0.66" DMD chip (2716 x 1528) or 0.47" DMD chip (1920 x 1080), but with the division of 4K images into 4 arrays and their shift. Of course, the simultaneous use of several different names for one technology may confuse some consumers. Today, wobulation technology for video processing in projectors use the following names: - JVC - e-Shift or eShift; - Epson - 4K Enhancement or 4KE; - Texas Instruments - TI UHD (informally). However, many prefer the more common name pixel-shifting or Pixel Shifting. Of course, some experts sometimes argue about the validity of using the 4K name for all these technologies. Indeed, pixel-shifting does not increase the physical number of pixels. But these disputes are linguistic in nature, because wobulation really enhances the clarity of the image in its visual perception. At the same time, this technology has radically reduced the cost of producing projectors with support for 4K resolution. As a result, today the market offers a wide range of models at a relatively affordable price.

HC 5050UB / 5050UBe

In 2019, the company introduced the new HC 5050UB / 5050UBe, which replace the 5040UB / 5040UBe (TW9400 for Europe) of 2016. Traditionally, the UBe model has a 4K wireless HDMI transmitter and costs $ 300 more. Of course, the novelty supports all functions of the previous model. In addition, it offers an improved pixel-shifting algorithm with higher efficiency, HLG support for HDR UHD content, new Digital Cinema color mode with full DCI-P3 color gamut and 18 Gbps HDMI 2.0 port., which supports 4K / 60p HDR games.

Lumen Output

New models provide 100 ANSI lm more compared to 5040UB (2,600 vs 2,500 lumens). But, the brightness value for Epson has some specific features due to the peculiarity of LCD projection technology. As known, the light from the source in 3LCD projectors is reflected from the mirrors of the optical unit. In fact, these dichroic mirrors perform the function of color filters, passing only a certain color (red, green and blue or R, G, B). After separation, the three light streams are directed to the corresponding LCD monochrome matrices, which, after modulation, form a black-red, black-green and black-blue image at the output. A prism unites them and forms a color image, transferring it further to the optical system, the lens and to the screen. Thus, all three color components are projected onto the screen at the same time, providing the same white light output and color light output (CLO). This aspect is an important difference between 1 chip DLP projectors and 3LCD models. The perfect balance between white / color light output really affects image quality. Of course, Epson actively uses this advantage, periodically presenting the results of various tests. Therefore, Epson, unlike other companies, always specifies two values in the specs of its models. In particular, the company indicates CLO (Colour Light Output) and white light output, once again reminding of this advantage. Of course, both of these values are always identical. The video at the end demonstrates the difference in color saturation of 3LCD vs 1-chip DLP models. Epson measures white light output in accordance with traditional ISO/IEC 21118 standard and CLO in accordance with IDMS 15.4 standard, which was first published in May 2012.

Improved pixel-shifting algorithm (4K PRO-UHD), HDR mode and lens

Epson 5050UB uses second generation of 4K-Enhancement, which is called 4K PRO-UHD. In particular, 4K PRO-UHD uses a pixel plate with tighter tolerances. As a result, the engineers have increased angle of the leading and trailing edges of the electronic shift pulse, reducing the delay between the bottom and the top of the pixel shift change. According to the company, this improvement reduces downtime, increasing the light output, color accuracy, and performance, in general. In addition, Epson indicates DCI 4K (4096 x 2160) for 5050UB vs 3840 x 2160 for 5040UB. Moreover, the company has improved HDR support. In particular, the new projector automatically detects HDR content, including HDR10 and HLG, and supports its setting from the menu. As known, this line of projectors uses a 3-axis motorized lens. Unfortunately, the previous models had a rather large lag. Now, engineers have reduced electrical noise of the control system, increasing the smoothness of its work. In addition, the improved system has an auto-centering control, which is activated by the “LENS” button.

Conclusion

Of course, the improved 4K image quality, excellent colors, good HDR performance and deep black provide an advantage of 5050UB vs 5040UB. However, the new model also has several drawbacks, including the huge size, the high price for Pixel Shifting technology, and a bit noisy in high setting. But in general, the model adequately continues the evolution of Epson 4K HDR projectors. In fact, today the price difference reaches almost 30%, which is probably a lot. But the visualization of all these pros is manifested only in complex video and in difficult conditions (highly dynamic or dark scenes on the big screen or in daylight, etc.). That is, when using a home theater projector. Therefore, the final assessment of the price / quality ratio depends on the individual preferences of the buyer and his budget. Besides, all these factors affect the choice of the optimal projector. Read the full article

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DLP vs LCD vs LCoS projectors

As known, the whole history of the consumer electronics development is accompanied by fierce competition. It forces companies to constantly increase competitiveness, expanding the functionality of their models and reducing its costs. Of course, the solution of this problem requires the active use of innovative technologies. As a result, companies are investing heavily in their development. As a consequence, today the market often offers similar in consumer qualities models using different technologies. LED LCD, OLED (LG), QLED(Samsung) and NanoCell (LG), Micro LED models in a TV segment perfectly illustrate this trend. High-tech projectors are no exception. Today, models with DLP, 3LCD, and LCoS (D-ILA, SXRD) projection technologies successfully compete in the market. In addition, the development of the segment with LEDs and laser LEDs as light sources initiated the rapid development of portable models of various form factors (pico, cubed, micro, pocket). Moreover, advances in precision technology for manufacturing aspherical lenses and reflective mirrors pushed the development of very popular Ultra Short Throw (UST) projectors, which are able to create huge high-quality projections at a distance of several tens of inches. LG PF1000UW perfectly demonstrates these possibilities. Of course, this situation provides a very rapid improvement of household appliances that pleases consumers. Unfortunately, this wonderful trend has a side effect. Today, the conscious choice of the optimal device requires some effort from the consumer. Of course, the price and functionality remain the main criteria. The price depends entirely on company policy and we cannot influence it. But assessing the price / quality ratio is sometimes a difficult task because of the abundance of offers, which often contain a marketing component. Therefore, even a simplified classification can partially simplify this task.

Operation principle

As known, DLP (Digital Light Processing) uses a semiconductor DMD (Digital Micromirror Device) chip from Texas Instrument with an array of micromirrors to reflect light. In fact, each micromirror corresponds to one pixel. The control signal tilts the micromirror at an angle of ± 12 °, forming a white or black dot on the screen. The frequency of control signals in modern models reaches several kHz. Today, the company produces a wide range of DMD, including, for example, DLP 2000 (0.20 "), DLP 2010 (0.21"), DLP 230GP (0.23"), DLP 230KP (0.23"), DLP 230NP ( 0.23"), DLP 3010 (0.31"), DLP 3310 (0.33") and DLP 4710 (0.47"). They support display resolution from 640 x 360 (nHD) to 1920 x 1080 (1080 p or Full HD). But DLP projectors form a color image on the screen, alternating a sequence of projections with different colors and creating the illusion of a color image due to the high frame rate. The color wheel with segments of different colors serves as a color filter. As known, 3LCD technology was developed by Epson. It uses the influence of electricity on the spatial orientation of liquid crystal molecules. In fact, its matrixes work in the same way as traditional LCD matrices in TVs. But unlike the DLP projector, the 3LCD models form a color image with the help of special prism from three mono-color images. The LCoS (Liquid Crystal on Silicon) projectors combine the best qualities of DLP and 3LCD technologies. Today, its versions of SXRD (Silicon X-tal Reflective Display) from Sony and D-ILA (Direct Drive Image Light Amplifier) from JVC are the most popular.

Contrast ratio

Of course, the image quality dependents on the contrast. As known, this value characterizes the ratio of the brightness of the brightest and darkest pixels. Specs of projectors or TVs contain it in the form of, for example, 60,000: 1. Accordingly, the contrast depends on the maximum brightness and depth of black. In fact, contrast provides depth and dimension of the image, which affect the realism of perception. Today DLP technology in the DLP and LCoS projectors provides higher contrast compared to LCD models. The use of reflection allows engineers to achieve very deep black due to the complete cut-off of light. LCD matrixes use the light pass and cannot ensure its complete blocking. But on the other hand, powerful lamp 3LCD projectors partially compensate for this factor with higher brightness. Many models use effective Auto Iris technology, which adjusts the aperture depending on the illumination of the scene in the frame.

Brightness and color

The brightness characterizes the light intensity in ANSI lm or lm. It has several names, including the light output or lumens rating. This value mainly depends on the type of the light source in the projector. Today, lamps and lasers provide maximum brightness. But the lamps are quite expensive and have a limited service life (4,000-6,000 hours). Laser LEDs provide high power and long service life, but are expensive (mainly due to expensive green lasers). LEDs have a very long service life (20,000-30,000 hours) and are relatively inexpensive, but do not provide sufficient brightness. In turn, brightness affects viewing comfort. Low brightness requires dimming the room to produce acceptable image quality. High brightness provides it even in daylight. Unfortunately, powerful lamps get very hot during operation and require efficient cooling. In turn, the noise during the operation of powerful fan reduces the viewing comfort. Therefore, the choice of brightness represents a trade-off between durability, dimming requirements and noise level. The type of light source mainly depends on the positioning model (portable, home theater, etc) and does not depend on technology. But in general, the 3LCD models often use lamps, and DLP and LCoS - semiconductor light sources (LEDs or laser LEDs). Color accuracy, color range and saturation depend only on the model class.

Motion Blur and Input Lag

As known, this effect is visualized in highly dynamic scenes. Companies solve this problem by increasing the frequency or using the interpolation method that TV manufacturers have been using for years. This technology is based on the formation of intermediate frames by the processor. Today, almost all leading companies use this technology and own indexes for TVs, including Motion Clarity Index (MCI), Clear motion rate (CMR), Picture Quality Index (PQI), Perfect Motion Rate (PMR), Motionflow XR, etc. Unfortunately, increasing the processor load significantly increases Input Lag. Therefore, some projectors automatically disable it in game mode. As known, Input Lag is especially important in games. This value in many modern projectors does not exceed several tens of milliseconds. But some projectors provide an unprecedented low Input Lag, which allows them to be positioned as game models. For example, the Input Lag of UST ViewSonic PX800HD does not exceed 16 ms with 3X Fast Input option. With other things being equal, DLP projectors are confidently leading in this aspect compared to 3LCD and LCoS models.

Rainbow and Screen Door Effects, and Dust Resistance

Rainbow effect appears as multicolored points along the contour of contrasting objects in the frame. It's caused by using a color wheel and shown only in 1-chip DLP projectors. Increasing the speed of its rotation reduces the effect. However, today companies successfully solve this problem in various ways, including, for example, using the innovative RGBRGB color wheel. Of course, LCD and LCoS projectors do not have this effect due to the lack of a color wheel. Screen Door Effect is a visualization of pixels on the screen at a short distance. The high pixel fill factorI duu to the minimum distance between micro mirrors in the DMD chip almost completely eliminates this effect in DLP projectors. Unfortunately, 3LCD models, especially inexpensive, form an image with this effect due to the rather large distance between the matrix crystals. However, more expensive models successfully compensate for it by high resolution. LCoS projectors form an image without this effect. Of course, dust significantly reduces the quality of optics, which is one of the main components of any projector. From this point of view, DLP projectors have a great advantage, because DMD chips are superbly sealed. 3LCD and LCoS models use sealed or non-sealed chips. More expensive models have additional protection.

Conclusion

1. DLP projectors have minimum dimensions and weight. As a result, this technology dominates among portable models. LCoS projectors are the most heavy and large. 2) DLP models provide excellent deep black, but only medium contrast due to the relatively low brightness. LCoS provides better contrast. 3) Low-cost 3LCD models require periodic cleaning of LCD matrices due to insufficient dust resistance. 4)The pixels on the matrices of 3LCD models can burn out over time. 5) With the same specs, today LCoS models are the most expensive, and DLP projectors have a minimal price. Of course, all these factors affect the choice of the optimal projector. This video offers the review of all technologies in modern projectors, including DLP vs 3LCD vs LCoS. Read the full article

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What is projector and its types?

The development of digital technologies for several decades provokes the rapid development of almost all segments of consumer electronics. Today, even a relatively simple household appliances is a complex multi-functional device. Smart coffee machines, robotic vacuum cleaners, washing machines, etc with Wifi support and complex algorithms for auto modes perfectly illustrate this trend. Of course, high-tech projectors are no exception. Modern projectors have evolved from simple devices to project an image into sophisticated digital equipment with huge media capabilities. The projector in the smartphone, miniature Pico and Cube projectors, 4K HDR models, etc perfectly illustrate this trend. Modern technologies have successfully solved the problems of their image quality, compactness, brightness, durability, noise and cost. Today, the market already offers 4K HDR models with a price range of $ 1,000 - 1,500. As a result, many consumers increasingly perceive the projector as an alternative to TV, increasing demand in this segment. Of course, companies are adequately responding to the market conditions by expanding their model lines. But the abundance of proposals sometimes complicates the choice of the optimal model. Therefore, even a simplified classification can help solve this problem.

The number of matrices

As known, the projector matrix provides filtering the luminous flux, passing or blocking it. Therefore, the matrix can form only a single-color image. This is fundamentally different from the matrix of the TV or monitor, which forms a color image. Three-color matrixes are not used in projectors for several reasons. First, almost all the first projectors used high-power bulbs with high heat dissipation for illumination. Therefore, the LCD matrix requires very powerful cooling, which affects the noise, size and cost. Secondly, the three-color matrix does not provide an ideal square pixel. A single-color matrix forms a color image, combining three separate images. 3-chip projectors combine the images and display the finished color picture. Single-matrix models alternately project mono-color images onto the screen, creating the illusion of a color image due to the high frame rate. PROS and CONS 1. 1-chip projector is more compact, but uses more complicated and more expensive matrix. 2. 1-chip projector provides lower brightness due to less efficient use of the bulb luminous flux. 3. Playback in 1-chip models is often accompanied by the rainbow effect due to the non-synchronous speed of changing the image color components. 4. A 1-chip projector provides a perfectly accurate pixel shape, which depends only on the projector optics. The accuracy of the borders of the individual pixels in the 3-chip projector depends on the accuracy of manufacturing and placement of the matrixes. This problem sometimes occurs in budget 3-chip models from lesser-known manufacturers.

Light source and sizes

Modern models use UHP (mercury) or powerful xenon lamps or semiconductor light sources (LEDs, LED lasers). Often, vendors use the name of a laser projector for models with LED lasers as a light source. Of course, this is not entirely correct. Developed in 1991, LDT (Laser Display Technology) technology really uses lasers to form images. The working prototype of the LDT projector was introduced in 1997, and the serial prototype in 1999. Today, these models belong to the professional segment of very expensive installation projectors. Laser in the name of DLP and LCoS models only indicates the use of LED lasers as a light source. Of course, the use of only one chip provides the advantage of DLP technology in terms of compactness. Combined with the LED light source, it provides the production of portable projectors. Their enormous popularity even provoked the formation of a separate segment of compact projectors (mini, pocket, cube, pico).

Projection image formation technologies

Modern projectors form a projection image using DLP, LCD or LCoS technology. DLP and LCoS with DMD chip use the reflected luminous flux, and the LCD works on the light pass. Of course, each of them has its own features, pros and cons, but all of them have been successfully competing in the market for many years. PROS and CONS of DLP and 3LCD projectors Some 3LCD models can have Screen-Door effect (SDE) The control elements of DLP matrices are located under the mirrors, but in the 3LCD matrices they occupy some space around the pixel, forming a small gap between them. As a result, the image on the screen can display the edging of each pixel, creating the effect of looking through the screen-door. In fact, this effect is sometimes present in budget models, regardless of technology. More expensive models usually use various compensation technologies to eliminate it. Some low-cost DLP projectors can display sharp color transitions (the “posterization effect”), generating digital noise when displaying a single-color field. This problem is caused by DMD chip control features. Almost all 3-chip projectors can have this problem due to the not perfect placement of the three matrices. As a result, this factor reduces the image clarity on the screen. But the optics quality affects the image clarity much more. A DLP projectors optical unit usually has a reliable seal and does not need air filters. On the other hand, other components, including the bulb and the board, require periodic cleaning from dust. Therefore, expensive DLP projectors of popular brands use filters. This video demonstrates the visualization of the rainbow effect (color artifacts along the contour of fast-moving objects) in 1-chip DLP projectors. Read the full article