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#Post#: 11--------------------------------------------------
LDR Sensitivity
DIR By: Dioni
Date: August 10, 2016, 9:18 pm
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[center]
HTML http://www.technologystudent.com/images2/ldr1.gif[/center]
The animation shows that when the torch is turned on, the
resistance of the LDR falls, allowing current to pass through
it.
Write Down your reasons to your answer in the poll below. ???
??? ???
#Post#: 39--------------------------------------------------
Re: LDR Sensitivity
DIR By: cefresto
Date: August 13, 2016, 3:10 am
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We can use resistors to adjust the sensitivity of LDR. The
preset resistor can be turned up or down to increase or decrease
resistance, in this way it can make the circuit more or less
sensitive. :))
#Post#: 40--------------------------------------------------
Re: LDR Sensitivity
DIR By: Junaimah
Date: August 13, 2016, 10:31 am
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To adjust the sensitivity of the LDR, We can use component;
resistors, to increase or decrease the resistance and because of
that our circuit will be more or less sensitive.
#Post#: 54--------------------------------------------------
Re: LDR Sensitivity
DIR By: butihenmy
Date: August 14, 2016, 4:42 am
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To increase the sensitivity of the sensor. Use the resistor. A
resistor is placed in series with the sensor and the output
voltage is measured either across the sensor or the series
resistor depending on the application of the circuit. To obtain
the largest variation in output voltage from the sensor
#Post#: 59--------------------------------------------------
Re: LDR Sensitivity
DIR By: cha sarmiento
Date: August 14, 2016, 10:20 am
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We can adjust ldr's sensitivity to light using resistors. A
Higher Value Resistor could work although it could potentially
affect the LED current too much too.
#Post#: 67--------------------------------------------------
Re: LDR Sensitivity
DIR By: darlyn
Date: August 14, 2016, 12:11 pm
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Other than using more sensitive LDR,
reducing the noise is a great idea also reduce the fixed
resistor in series with the sensor will do. This may be done by
putting other resistors in parallel with it. This will increase
the voltage drop across your sensor making it more responsive to
the same input. Beware however. This fixed resistor is probably
limiting the current to the sensor protecting it from an
overload situation.
Another Possible Methods to increase the sensitivity of a sensor
would be:
(It can be on Physical Environment - )
1. One is to focus or channel the light in the direction of the
sensor. This will ensure the strength of your signal.
2. Another is to keep the sensor in as close proximity to the
light transmitter as possible. This will reduce noise.
3. A third is to remove as much noise from the system as
possible. That is, reduce the amount of ambient light in your
system (and thus, reduce noise).
(That third one will probably do the most to enhance the
sensitivity. )
or Electronically ...
1. Find a way to amplify the light heading to the sensor, which
would, in turn, amplify the change in the light going to the
LDR.
2. Find a way to amplify the signal coming from the LDR.
In both cases, but especially when amplifying the signal out of
the LDR, you want to filter out as much noise as possible.
I hope I gave you the answer that you wanted or expecting to
have/read.
#Post#: 81--------------------------------------------------
Re: LDR Sensitivity
DIR By: justine
Date: August 14, 2016, 9:37 pm
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Maybe we should use resistor po?
Sabi po daw kasi the preset resistor can be turned up or down to
increase or decrease resistance, in this way it can make the
circuit more or less sensitive. :)
#Post#: 89--------------------------------------------------
Re: LDR Sensitivity
DIR By: Kayla Jem Juliano
Date: August 14, 2016, 9:57 pm
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I think, we should use resistor po. According to my source ;D
The preset resistor can be turned up or down to increase or
decrease resistance, in this way it can make the circuit more or
less sensitive. ;)
#Post#: 92--------------------------------------------------
Re: LDR Sensitivity
DIR By: jeffrelyn V. Banar
Date: August 14, 2016, 10:03 pm
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Resistor po.
Because when the light level is low the resistance of the LDR is
high. This prevents current from flowing to the base of the
transistors. Consequently the LED does not light.However, when
light shines onto the LDR its resistance falls and current flows
into the base of the first transistor and then the second
transistor. The LED lights.
The preset resistor can be turned up or down to increase or
decrease resistance, in this way it can make the circuit more or
less sensitive.
#Post#: 99--------------------------------------------------
Re: LDR Sensitivity
DIR By: carrenjoy
Date: August 15, 2016, 7:58 am
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When the light is absorbed by the material then the conductivity
of the material reduces. When the light falls on the LDR, then
the electrons in the valence band of the material are eager to
the conduction band. But, the photons in the incident light must
have energy superior than the band gap of the material to make
the electrons jump from one band to another band (valance to
conduction). Hence, when light having ample energy, more
electrons are excited to the conduction band which grades in a
large number of charge carriers. When the effect of this process
and the flow of current starts flowing more, the resistance of
the device decreases.
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