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Using light to detect pulse (heartrate monitor) & automatic taps

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Using light to detect pulse (heartrate monitor) & automatic taps

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Does heart rate monitors on fitness trackers accurate ?? 

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Does heart rate monitors on fitness trackers accurate ?? 

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https://youtu.be/uWnaqsLSl8c

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CNET News - Are heart rate monitors on fitness trackers accurate?

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https://youtu.be/NPaV4KxQbtQ

Video

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In your group:

1) Read the article & watch the video.

Reflect on how does light play a role in the application / device?

2) How does the invention / device work?

3) In your opinion, suggest how does it benefit or destroy mankind?

Note: Write down your reflections and findings under the tab assigned to your group.

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Laser light is shone on the label surface and its reflection is captured by a sensor (laser photo detector) to read a bar code. A laser beam is reflected off a mirror and swept left and right to read a bar code Using laser allows reading of distant and wide bar code labels.

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Light Plays a role in an automatic door when light is passed from a sensor on one side of the door's gap to the receiver on the other side. When there is nothing passing through the door , the beam makes one continuous line and when someone walks through the door way , the light beam is cut and light is temporarily undetected by the receiver. In response the doors open again to prevent closing on the person

In my opinion the invention is very useful because we would no longer require to do anything for the door to open just stand Infront of it and it will automatically open but it might be bad for some people in hurry as the door takes time to open and some people in hurry might bump into the door

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Automatic doors as you know allow people to enter and exit without the need to touch the door itself, in these times of increased hygiene since the pandemic a touchless option for entrances can help to stop the spread of germs and think how many people touch a door throughout the day less option for entrances can help to stop the spread of germs and think how many people touch a door throughout the day.

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the automatics sink works by near IR light , a certain amount of light and hand placements it needs to be in front of the sensor , the hand distance also needs to be 1-2 inches from the automatic sink. they promote hygiene by reducing the spread of germs.

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the light plays a big part in tye smoke detectors as it contains infared

light.when there is fire,smoke enters the detector and blocks the beam of light so the photocell can on longer produce an electric current

It helps mankind as it helps make people there homes safer

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Table of Contents

smoke detector, device used to warn occupants of a building of the presence of a fire before it reaches a rapidly spreading stage and inhibits escape or attempts to extinguish it. On sensing smoke the detectors emit a loud, high-pitched alarm tone, usually warbling or intermittent, and usually accompanied by a flashing light. There are two types of smoke detector: photoelectric and ionization. Photoelectric smoke detectors utilize a light-sensitive cell in either of two ways. In one type, a light source, e.g., a small spotlight, causes a photoelectric cell to generate current that keeps an alarm circuit open-until visible particles of smoke interrupt the ray of light, breaking the circuit and setting off the alarm. The other photoelectric detector, widely used in private dwellings, employs a detection chamber shaped so that the light-sensitive element cannot ordinarily "see" the light source (usually a light-emitting diode [LED]). When particles of smoke enter a portion of the chamber that is aligned with both the LED and the photocell, the particles diffuse or scatter the light ray so it can be "seen" by the photocell. As a result a current is generated by the light-sensitive cell and the alarm is triggered.

Ionization detectors employ radioactive material-in quantities so tiny they are believed to pose no significant health hazard-to ionize the air molecules between a pair of electrodes in the detection chamber. This enables a minute current to be conducted by the ionized air. When smoke enters the chamber, particles attach themselves to ions and diminish the flow of current. The reduction in current sets off the alarm circuit.

Photoelectric detectors respond faster and more effectively to the large smoke particles generated by a smoldering, slow-burning fire. Ionization detectors respond faster to the tiny smoke particles released by a fast-burning fire. For this reason some manufacturers produce combination versions of detectors. Many fire-prevention authorities recommend the use of both photoelectric and ionization types in various locations in a private home. Either type of detector can be powered by batteries or by house current.

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Smoke detector | Fire safety, Carbon Monoxide, Battery-powered

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Smoke detector, device used to warn occupants of a building of the presence of a fire before it reaches a rapidly spreading stage and inhibits escape or attempts to extinguish it. On sensing smoke the detectors emit a loud, high-pitched alarm tone, usually warbling or intermittent, and usually

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1)the green led flashes hundreds of times every second

2)heart rate monitors is work by the green light that travels through the skin and detects the heartbeat in our vessel from the heart

3)this benefits by keeping us healthy and active.

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laser weapons uses light particles. The photons pass through a gain medium a material that creates a cascade of additional photons which rapidly increases the number of photons. All these photons are then focused into a narrow beam through a beam director. Some weapons required a cooling system as sometimes the weapon generates significant heat and a cooling mechanisms to maintain performance.

2)lasers travel at the speed of light, providing instant passage of energy to the target as this is crucial to block the signal for missiles or aircraft.

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smoke alarms have a small amount of radioactive material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm.