Sharp EL-9900 Calculating Illuminance and Luminous Intensity, Entry of distance and angle Return

EL-9900 Graphing Calculator

Calculating Illuminance and Luminous Intensity

Enter the luminous intensity of the luminous source, the distance, and the angle between the perpendicular line and light ray, to find the illuminance of the illuminated side. Conversely, find the luminous intensity of the source from the illuminance of the illuminated side.

Calculation
i =	l	cos θ	l =	r	2	i		Luminous Intensity l
		r2		cos θ				θ
l : luminous intensity [candela]						i : illuminance [lux]		r
r : distance [m]						θ	: angle [˚ ]	Illuminance i

FLOWCHART

PROGRAMME LIST(REAL MODE)

Start

A start

Selection of type

	Y
		S = 1
			N
		S = 2					LUX
CANDELA			A
To subroutine					To subroutine
Entry of						Entry of
illuminance				luminous intensity
Calculation of					Calculation of
luminous intensity						illuminance
Display of						Display of
luminous intensity						illuminance

End

Subroutine

DISTANCE

Entry of distance and angle

Return

Enter 1 or 2.

To calculation of luminous intensity.

To calculation of illuminance.

Jumps to subroutine

DISTANCE.

Enter illuminance or luminous intensity.

Illuminance or luminous intensity calculated.

Illuminance or luminous intensity displayed.

Subroutine for entry of distance and angle.

Entry.

Returns to calling program.

Title : CAND LUX

Deg

Label START ClrT

Print "CANDELA=1 LUX=2 Print "SELECT 1 or 2 Input S

If S=1 Goto CANDELA If S=2 Goto LUX Goto START

Label CANDELA

Gosub DISTANCE Print "Input LUX Input L

L	I
R2	I/cos θ C
Print "CANDELA

Print C End Label LUX

Gosub DISTANCE Print "Input CANDELA Input C

C K

K cos θ /R2 L Print "LUX Print L

End

Label DISTANCE Print "Input DISTANCE Input D

D R

Print "Input ANGLE Input A

Aθ

Return

PARAMETERS

Name of parameter	Content	Name of parameter	Content
I	illuminance of illuminated side	θ	angle
K	luminous intensity of luminous source	A	input of angle
R	distance	L	input and calculating luminous intensity
S	selecting calculation type	D	input of distance
	(S=1: calculation of luminous intensity)
		C	input and calculating illuminance
	(S=2: calculation of illuminance)

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