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70

Your calculations are correct in essence. For a 1440p60Hz signal, you have a data rate of 5.8Gbps once you allow for blanking time as well (non-visible pixel border in the image output). For HDMI/DVI, a 10/8b encoding is used, which means effectively although you have say 24bit of colour data per pixel, actually 30bit is sent as the data is encoded and ...


20

Modern computers are surprisingly fast. People will happily load up full HD 30fps videos without realising that that involves billions of arithmetic operations per second. Gamers tend to be slightly more aware of this; a GTX 1060 will give you 4.4 TFLOPS (trillion floating point operations per second). Please explain if my calculations are wrong and how is ...


18

Actually, many displays do use LEDs - but as far as I know, exclusively for extremely large displays. Just do a search for 'LED signage' and you'll see a whole sub industry around displays made from LEDs. And I mean real, full motion video displays. You've probably seen one on a billboard at some point. They also make, or at least made, small displays ...


17

Pixels per mm = 400/61.2 = 6.536 Yup. Number of pixels in one image = 65.36 x 65.36 = 4272 pixels Well, you mean pixels per icon. But even so, you cannot produce fractional pixels, so your number should either be 65 x 65 or 66 x 66. And this leads to a further simplification. Why not make your icons 64 x 64? This will simplify address calculations for ...


15

That is called a zebra strip or Elastomeric_connector. It is made from silicone rubber with conductive carbon particles in them. This is used to make sure the connection between the PCB and glass is flexible, as both are neither thermally nor mechanically compatible at all. Also, as it doesn't rust or really react with anything galvanically at all it ...


15

Quadrophonic systems have four speakers. "Balance" therefore means you have to handle front to back as well as left to right. The "balance" control on this system looks like a joystick. The display above it is an edge lit plexiglas picture. It is static (doesn't change.) The red spot is an LED behind the plexiglas. It is mechanically coupled to the ...


14

MIPI and LVDS panels are quite different. They are different ways of sending a RGB, DE, Hsync, VSync signal to a panel. Older (lower res) panels would accept these digital signals directly so RGB24 would have 27 signals, and they would toggle at the pixel rate. LVDS is quite straight forward, and is just parallel data serialised 7:1. The RGB, DE, and syncs ...


13

While EInk has patented a black particle in white fluid display, the shipping article is a dual particle system consisting of white particles of one charge and black particles of opposite charge. These are electrophoretic displays - which is just a fancy way of saying "moving particles through a fluid with an electric field". The particles themselves come ...


12

It's a 7-segments display. Unlike the dot-matrix character displays kevlar refers to these are most often not intelligent module. Most dot matrix displays have an HD44780-compatible controller which you simply can write ASCII codes to, but a 7-segment LCD will often be just the glass, with connections for segments and a number of backplanes (often up to 4). ...


12

LCD display without back-light is the only possible solution on these conditions. Something like this: Here is some example data sheet: Link to PDF


12

The OP asked how a VGA cable works, so I'll start with the wiring for a standard cable, which is a DE-15 15-pin connector (sort of like the DB-9 connector used for RS-232, but with an extra row): H-SYNC and V-SYNC stand for horizontal and vertical sync. The rest are self-explanatory. H-SYNC and V-SYNC are digital (TTL) level signals, active low, and the ...


11

The Double-dabble technique converts binary to BCD by repeated shifting. Each repetition halves the remaining binary number and doubles the BCD number, after the complete binary value is shifted the result is obtained. After each shift a correction is applied to each 4-bit BCD column (or those having more than 3 bits shifted in by that point). This ...


11

How does a newspaper display shades of grey? They don't have 10000 different colours ink do they? Get a magnifying glass and see: They put black dots in groups, many dots are dark, few dots are light. That's exactly how this works. One such bubble can only be black or white, but because there's 100's of them in a square cm they can turn on only a few to get ...


11

The link between display card and LCD panel is carried over several high-speed differential pairs using TMDS signaling, usually called "lanes". Typically four lanes are used, so one can say that the bus is 4-bit wide. For some more details there is a stackhexchange answer. Each LCD panel model is usually produced with several interface incarnations, so one ...


11

Make life simple for yourself by making the icons 64×64 pixels. Draw a border around them if you want them to look larger. With the 16-bit color format, this only requires 8 kB per icon, or 400 kB for the set of 50. One simple form of compression is to use a color table instead of storing every pixel's color directly. 16 colors is frequently more ...


10

The left hand side of the board in the 2nd to last picture contains two PIFAs (Planar inverted F antenna). Looks like one is 2.4 GHz and one is 5 GHz. It appears that the ZBS242 chip is a Samsung SOC with a built in IEEE 802.15.4 ZigBee radio. I can't find much information about it, and the pages I have found are in Korean. Figures. http://eplus.co....


9

Seems to be what NEC refers to as VIT, Value Integrated TFT Technology. Alternatively known as SoG, System on Glass. They differentiate it from Chip on Glass or Chip on Film/Tape. But the tech isn't that old. A press release shows maybe 2007. Due to the high electron mobility of the low-temperature polysilicon used in VIT technology, high-speed ...


9

If we redraw your circuit without the diodes, we have this: simulate this circuit – Schematic created using CircuitLab Now imagine you drive Column-1 High and Row-1 Low (and Column-2 and Row-2 are Hi-Z) because you're trying to activate L1 in one direction. You'll find that you'll also have current flowing through L2, L4 & L3 since the 3 of them ...


9

The 74LS47 shows the following: $$ \begin{array}{ccccl} D & C & B & A \\ 0 & 0 & 0 & 0 & \rightarrow 0 \\ 0 & 0 & 0 & 1 & \rightarrow 1 \\ 0 & 0 & 1 & 0 & \rightarrow 2 \\ 0 & 0 & 1 & 1 & \rightarrow 3 \\ 0 & 1 & 0 & 0 & \rightarrow 4 \\ 0 & 1 & 0 & 1 &...


9

More about color depth Expanding on Dave Tweed's answer, you can do even better than what he showed. Here is the same large-size original he used: Cropped to be square and shrunk to 64 x 64 pixels but using full (8 bit per red, grn, blu) color yields: Rounding the color information from 8 bits per channel to 6 bits results in: That is what your display ...


8

The problem is you have on and off mixed up. The pnp transistor will be at cutoff when the output is high, not low. So you are turning both of your displays on during the 1000us wait.


8

Quick bit of Wikipedia leads to: http://en.wikipedia.org/wiki/Phosphor#Standard_phosphor_types "P1" is a zinc silicate which is found natually occuring in an ore. I suspect this was the first kind of phosphorescent material to be used in CRTs, and as it's naturally occuring it may be the cheapest. In most monochrome CRT applications (especially osciliscopes)...


8

LVDS -> Low Voltage Differential Signalling is the actual voltage and impedances on the physical wires. There are different voltage levels even within the MIPI standard, so pay attention to those. MIPI is the format of the how the various bits are located relative to other bits and signalling and start and stop sequences inside the data stream. In some ...


8

Each pixel will require 18 bits X 3 (for R, G and B) = 54 bits Your estimate is incorrect. The "18 bits" value is per pixel, not per colour. The red, green and blue channels each have a maximum bit depth of 6 bits (64 different values), 18 bits in total. This display controller also supports a 16-bit mode (where pixel data only has 5 bits for red, 6 for ...


7

The up-voted and accepted answer is not even wrong. It's pure guessing. There are no individual pockets in LCD panels. They are two parallel glass plates with special films applied. The plates are held apart with tiny beads (PMMA or Glass)- on the order of 10's of microns. When two adjacent pixels are set at different voltage levels the LC between the ...


7

Actually this is a very common arrangement. Each digit has its anodes connected together, and the segments for all digits have their cathodes connected. The controller enables one of the common anodes, drives the segments, and waits, then turns off the cathodes and moves on to the next common anode. This arrangement and control method is called multiplexing, ...


7

For a well done project? Very, and Expensive. You would need to source a proper Mini DisplayPort adaptor, then figure out how to turn a digital dvi signal to display onto two monitors while the computer only sees one. And if you want thunderbolt? Forget it. Outside of any conceivable student range or pricing. According to MSI, a huge manufacturer of ...


7

The capacitor filters noise, making the voltage at V0 more stable. A capacitor resists changes in voltage. The rate of change of voltage, current, and capacitance are related by: $$ I = C \frac{\mathrm{d}v}{\mathrm{d}t} $$ The larger the capacitance, the more current required to make a change in voltage. Since there is only so much noise current, the more ...


7

OK, after being pointed into the direction of gas-discharge displays (e.g. nixie tubes), I found out that this is a case of 'cathode poisoning'. The images on the linked page match with what could be seen on my display (dark regions on the segments). The remedy is to drive the segments with a current 2 up to 10 times higher than what is normally used. The ...


7

"Trick" question: it's an analogue device, so it is not limited to any particular fixed number of colours and can continuously vary between those colours in its gamut. Analogue colour depth is probably best considered in terms of signal-to-noise ratio or contrast ratio. Edit: you also need to consider how well the colours correspond to the source, see "...


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