APDS-9005-020 Avago Technologies US Inc., APDS-9005-020 Datasheet - Page 11

• Manufacturer Part Number: APDS-9005-020
• Description: AMBIENT LIGHT SENSOR 6CHIPLED
• Manufacturer: Avago Technologies US Inc.
• Type: Ambient Light Photo Sensorr

Specifications of APDS-9005-020

• Package / Case: Chip LED-6
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Product: Ambient Light Sensor
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 516-1717-2

Appendix B: Optical Window Design for APDS-9005
2.0 Optical Window Dimensions
To ensure that the performance of the APDS-9005 will not
be affected by improper window design, there are some
constraints on the dimensions and design of the window.
There is a constraint on the minimum size of the window,
which is placed in front of the photo light sensor, so that
it will not affect the angular response of the APDS-9005.
This minimum dimension that is recommended will
ensure at least a ±35° light reception cone.
If a smaller window is required, a light pipe or light guide
can be used. A light pipe or light guide is a cylindrical
piece of transparent plastic, which makes use of total
internal reflection to focus the light.
The thickness of the window should be kept as minimum
as possible because there is a loss of power in every
optical window of about 8% due to reflection (4% on
each side) and an additional loss of energy in the plastic
material.
Figure B1 and B2 illustrate the two types of window
that we have recommended which could either be a flat
window or a flat window with light pipe.
Figure B1. Window Size Determination for Flat Window
Figure B2. Window Design of Flat Window with Light Guide

Table 1 and Figure B3 below show the recommended
dimensions of the window. These dimension values are
based on a window thickness of 1.0mm with a refractive
index 1.585.
WD
Figure B3. Recommended Window Dimensions
WD:
D1:
T:
L:
D2:
Z:
Table 1. Recommended minimum dimension for optical window
All dimensions are in mm
The window should be placed directly on top of the light
receiving area (active area) of the photo sensor to achieve
better performance and if a flat window with a light pipe
is used, dimension D2 should be 1.2mm to optimize the
performance of APDS-9005.
The recommended minimum window dimension is based
on the assumption that the center of the window and the
center of the light receiving of the photo sensor are the
same. It is recommended that the tolerance for assembly
be considered as well. The recommended minimum
window size which will take into account of the assembly
tolerance is defined as:
D1 (min + assembly tolerance) = D1min + 2*(assembly
tolerance) (Dimensions are in mm)
D2 (min + assembly tolerance) = D2min + 2*(assembly
tolerance) (Dimensions are in mm)
(T+L+Z)
WD
.5
.0
.5
3.0
Light Receving Area
Working Distance between window front panel
& APDS-9005
Window Diameter
Thickness
Length of Light Pipe
Light Pipe Diameter
Distance between window rear panel and
APDS-9005
D1
0.5
.0
.5
.0
Z
Flat Window
(L=0.0)
Z
APDS-9005
L
T
.05
.5
3.45
4.5
D1
Top View
.0/.
D1/D2
-
-
-
with Light Pipe
Flat window
.0/.5/0.5
T/L/Z
-
-
-
D2 D1