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27

When I have a camera, that can take still images at 10fps with a mechanical shutter, why doesn't it mean the sensor can take images at 10fps electronically without producing rolling shutter? In order to understand why, we have to take a look at a typical 3T(ransistor) pixel: This 3T pixel can be used with rolling shutters, but not with (electronic) global ...


26

There is one overriding requirement for deep-space missions: reliability. In general NASA Preferred Parts are quite stodgy, because the overriding need is for a mature, well-understood technology. Cutting-edge technology that doesn't work is frowned upon under the circumstances. So 10-year-old image sensors are about what you expect. Additionally, if you ...


16

It comes down to market size. Where is the demand for such cameras and do the number of sales justify the production set up costs? You can get an infra red conversion to standard type DSLR cameras (eg Do It Yourself Digital Infrared Camera Modification Tutorials) and you can convert the camera to a 'full spectrum' type which takes in some ultra violet. (see ...


16

There are two parts to this: First, rolling shutter can still occur with (some, see note) mechanical shutters. However, this is only at short exposure times. The shutter is built out of two curtains. Before the exposure, curtain 1 is in front of the sensor. When the exposure starts, curtain 1 moves down (or up or whatever) and starts exposing the sensor. At ...


11

You will need the following things to make a simple digital camera: A camera module. These contain the actual CCD (or CMOS) imaging chip, and optics all nicely integrated. There are a few options available. For example the LinkSprite module. The good thing about this is that it contains an on board JPEG compressor, so it actually outputs the image already ...


11

You seem to be under the impression that the quality of photos taken in space is limited by the sensor resolution, which is not the case. Equally important factors are the sensor sensitivity, which gets worse as you increase the pixel count, and the robustness of the optical system. Simply put, if you were to send a 10MP DLSRs camera on Jupiter, it wouldn't ...


10

If you have 0 V across it it will be safe. Mainly because you mention it hasn't been used for a year. If you would have discharged the capacitor through a resistor (or even short it out) the voltage will go pretty low, but may rise again if you remove the short circuit. But if you measure nothing after a year that effect is completely gone. Now the ...


10

Regardless of which chip is which, it is unlikely that there is an ethernet connection in there anywhere. The processor talks to the wifi module directly rather than over ethernet. Sony wouldn't include the ethernet chips and transformers if there's no external ethernet connection If you need a wired ethernet connection, you will have to get yourself a ...


10

It's not a strong electric shock else you'd be shouting that from the rooftops so, I am presuming you mean something more like an irritating tingle. Based on that assumption I would suggest that the power supply is leaking a little AC current from the power side through to the DC side and this side is also connected to the metal casing around the cameras. ...


9

Microprocessors and webcams (usually) do not have a dedicated symbol. There are basically rectangles with pins attached to them, like latches. A symbol for a microphone can be found here.


8

CCD's are made from Si which has a bandgap of 1.12 eV. This means that it can sense a limited amount of thermal radiation at about ~ 1 um wavelength or shorter. This is called Near IR or NIR. Thermal sensors in the meantime, sense thermally emitted radiation ~ 10 - 14 um wavelength (this is the radiation emitted by a warm body at ~ 300 kelvin). The ...


8

First of all: standard CCD sensors are sensitive to wavelength far beyond 700nm. As much as I know Si-sensors are even more sensitive for near-IR light than for visible light. Of course it changes for much larger wavelengths: One condition for light being detectable is that photons have enough energy to create a hole-electron-pair. This energy threshold is ...


8

I'd say the difference is 20% due to hardware and 80% due to software. The hardware side The smartphone probably has better optics and wider aperture; The smartphone has focusing. The Pi has fixed focus (so it's only good for objects more than 1m away, see hyperfocal distance). But that means that most objects, especially the close ones, are somewhat ...


7

Camera flash capacitors are constructed to have low resistance, and more importantly, low inductance, so that they can deliver their energy to the flash tube as quickly as possible — which means achieving a fast risetime on the pulse of current. The internal connections are also made more robust in order to avoid localized heating as a result of the ...


7

Touching a pin does not eliminate the circuit issue, it just hides it. Your circuit still have an issue, and a big one - this particular CAM_DATA[7] bus signal has insufficient timing relative to bus clock, likely an insufficient hold time. A finger, or tweezers, or scope probe all do have some capacitance, 3pF, 5pF, or 10pF. Attaching a probe (or touching a ...


6

It's most likely discharged, but to be safe: Using one hand: Snip the wires connecting the capacitor Short the leads of the capacitor with a screwdriver or by pressing the leads together with pliers You can now be sure it is safe


6

This isn't really an electrical engineering question, but the short answer is that your eye has limitations. All light is a subclass of a larger form of energy called electromagnetic radiation. You can't see EM radiation with a wavelength shorter than around 730 nanometers, or what our brains perceive as red. However, your camera doesn't have the same ...


6

Depends on the camera and how "raw" it is. A raw CMOS sensor usually spits data out in a 16-24 bit framed parallel bus. It's the same kind of system you see on the input of HDMI transmitters or some LCD panels. There is usually also an I2C interface for controlling the sensor. Other sensors use the same thing but transmit via LVDS (this is very common with ...


6

It's probably differential GPS, although it might just be two independant regular GPS recievers (hence the minimum suggested distance). All of the product photos show it outdoors, another requirement for GPS. GPS can work at extremely high speeds once it's acquired a good lock; consumer units are not "allowed" to operate at more than 512m/s (about 1800kph) ...


6

It sounds like you are talking about Thermal Infrared, 10um - 14 um wavelength which corresponds to a black body temperature of 300 K. This is what is typically used to image and detect the body heat of mammals. The detector here are either MCT (Mercury Cadmium Telluride) cooled detectors or Bolometer based. The answer is yes, the ambient visible light ...


6

Both your existing answers are valid, but may be taken in combination: Simple Si sensors are good for visible and NIR and are common and therefore cheap. Modifications to the imaging system are required in many cases as the IR is normally blocked because it's undesirable. See for example Canon's EOS 20Da. Silicon sensors are fairly easily adapted to UV use ...


6

I doubt it at 10Mhz, you could think of propagation delay, or the time it takes your signal to travel down your outer layer traces as around 150ps/inch. At 10Mhz you're looking at a 100ns clock period. From that you can see that a few cm will hardly make a difference for you. Your concern about matching is really about making sure you meet your setup ...


6

This is called an image sensor. This particular image sensor in your picture is a CMOS image sensor, commonly found in pretty much anywhere a small to medium sized camera is used, as well in some big and/or professional gear. The camera in your phone is almost certainly a CMOS image sensor. It is probably also the type of sensor captured the image you ...


5

Some hints from experience: try to somehow to identify the CCD sensor and get the datasheet. Without that it will be very hard to do anything reasonable. The only work around would be to analyze live signals while the scanner is still working. try to reuse as much of the electronics as possible. E.g. level shifters, signal conditioning. Also the ADC may be ...


5

The feasibility of transferring live video over Bluetooth from an Android mega is low but not zero, being constrained by the following: Bluetooth practical throughput limitations: Bluetooth 1.2 = ~ 700 Kbit / sec Bluetooth 2.0+EDR = ~ 2.1 MBit / sec Bluetooth 3.0+HS, 4.0: These use a separate wireless path (e.g. 802.11, like WiFi) for the high speed data, ...


5

Background: One of the more common things in the last decade is laptop (and some desktop) producers using usb as a catch all bus, instead of dedicated hardware for peripherals. Instead of designing and including sometimes space intensive hardware for many parts, they just design with bridges with a few usb ports in mind, and hubs to expand them. Everything ...


5

I'm not saying that you will NOT find this data sheet. Do keep trying. But in general, data sheets for SOC's, cameras etc. that are used in the handset market are generally only released on NDA and are not generally available. You can see this on sites like Spark fun that sell the modules but can't supply the data sheets. However, there are a couple ...


5

Note: Some of the information below is anecdotal, since my measurements use a Canon 1D Mark III dSLR, rather than specific light-sensing instrumentation I've just started work on a strobe softbox for my own product photography studio use, especially motion capture (multiple exposure of moving parts in a single frame): I will be using RGB LED strips to get ...


5

For both visible and bolometer type, the reason they are cheap is because they can leverage the economies of scale in the silicon business. As soon as you get out into wavelengths (i.e. energies) that need other technologies (InGaAs as mentioned, InSb) you're talking 2" and 3" wafers at best, nothing like the pizza sized silicon wafers used to make chips ...


5

The general term would be an image sensor, the underlying technology would either be a CMOS sensor (a.k.a. active pixel sensor), or a charge coupled device (CCD). I have no idea which of the two it is based on your image.


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