Device for evaluation of illumination level of working places equipped with PC “Luxon” Supervised by: Borovitskyi V.N. Kondratenko D.U. deka@email.ua Project.

Device forDevice for evaluation ofevaluation of illuminationillumination level of level of working placesworking places equipped with PCequipped with PC

“Luxon”“Luxon”

Supervised by:

Borovitskyi V.N.

Kondratenko D.U.

deka@email.ua

Project by:• Podolyan D.A.•Pivtorak V.V.

NATIONAL TECHNICAL UNIVERSITY OF UKRAINE “KPI”INSTRUMENT MAKING FACULTY

OPTICAL AND OPTOELECTRONIC DEVICES DEPARTMENT

"Люксон" 230.05.2007

General descriptionGeneral description

The main function of Luxon is measuring the level of illumination of working places that have

computer displays, which bring out light signal information about belonging of the illumination

level to given limits.

"Люксон" 330.05.2007

Circuit diagramCircuit diagram

A photo resistor was used as a sensing element, that responded to illumination. It’s spectral sensitivity diagram is maximally close to the human eye one, The photo resistor is placed in the circuit diagram as a potential divider. The signal from the divider passes on to the input of the ADS of the microcontroller. After that the signal is being threshold according to the program. One or few LEDs turn on, depending on the level of illumination.

"Люксон" 430.05.2007

CalculationsCalculations

The illumination characteristics of the photo resistor were measured for calculations of the power dividing elements by means of a light meter and a digital tester.

"Люксон" 530.05.2007

CalculationsCalculations

The luminous characteristic of the photo resistor is nonlinear. This was kept in mind, when the thresholds were getting set and the device was tuned.

"Люксон" 630.05.2007

SoftwareSoftware

"Люксон" 730.05.2007

Developing processDeveloping process......The device development began with getting radio elements. This helped to make a decision on what size should the device have.

A screwdriver case was decided to use as a device shell because of it’s appropriate size.

"Люксон" 830.05.2007

Developing processDeveloping process......

A two sided circuit board was bought then.

"Люксон" 930.05.2007

Developing processDeveloping process......

Later development was held on the computer in “Kompas” . The positioning of the outer elements and the sizes of the support for the photo resistor were chosen. After this all the necessary openings were cut out in the board. The details were installed.

"Люксон" 1030.05.2007

Developing processDeveloping process......

The final settings and tests were made.

"Люксон" 1130.05.2007

Developing processDeveloping process......

A cover for the device was developed for better appearance.

"Люксон" 1230.05.2007

ResultsResults

"Люксон" 1330.05.2007

DemonstrationDemonstrationWhen the illumination level is normal (from 300 to 500 lux)

A green LED is on.

"Люксон" 1430.05.2007

DemonstrationDemonstrationWhen the illumination level is low (less than 200 lux) a blue LED turns on, when it is high (more than 600 lux) – the red one turns on.

"Люксон" 1530.05.2007

DemonstrationDemonstrationFor better convenience two more ranges of illumination were added– from 200 to 300 lux (blue and green LEDs turns on) and 500 to 600 lux – green and red LEDs turn on.

"Люксон" 1630.05.2007

Thank you for your attentionThank you for your attention

CONTACT US:

National Technical University of Ukraine “KPI” Optical and optoelectronic devices department Kyiv 03056, prospekt Peremogy 37http://ooep.ntu-kpi.kiev.ua/

Project developed within the limits of subject “Microprocessors and computers” http://ooep.ntu-kpi.kiev.ua/microcontrollers/