LASER EMITTING MODULE,
WINDOW CAP, LASER POINTER,
AND LIGHT EMITTING MODULE
Kara Lambson
OPT 310
General Info
• Title: Laser Emitting Module, Window Cap, Laser Pointer,
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and Light Emitting Module; US 7447243 B2
Filed: August 29, 2005
Issued: November 4, 2008
Inventors: Masayoshi Aoshima, Eiji Otani (JP)
- Aoshima: 9 other patents
- Otani: 17 other patents
Assignee: Sony Corporation, Tokyo (JP)
- ~158,000 patents
Need for Invention
• Light emission from laser pointers restricted to >1mW for
safety reasons
• Low relative visibility from red light laser diode, difficult for
human eyes to discern indicated position which is being
illuminated by the pointer during presentation using
projector
Invention
• Uses: Spot light for pointing to referring portion during
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presentation; point out any portion on the screen from a
distance with easier handling than a rod-like pointer, and
compacter in size
Light emitted from laser diode excited solid-state laser
medium to generate lights of different wavelengths
Convert wavelength via non-linear optical element to emit
a laser beam of short wavelength by second harmonic
generation
Alternative laser pointer using laser beam in range of
wavelengths that can provide higher relative visibility
factor than red light
Dissipated heat management
Prior Art
• Same solid state laser with many of the same elements
and wavelength output
• Efficiency dependent on temperature  temperature
control device required
• Deterioration of the visibility of a region spot-lighted while
laser beam varies unstably due to temperature
• High failure rate due to all elements arranged in single
casing (dust during assembly)
Distinction from Prior Art
• Contains heat sink to dissipate heat from laser diode and
optical resonator  stabilized temperature
• Airtight material to ensure window cap and internal
elements stays dust-free  increased reliability and
service life
• Surface optical filter for selection of wavelengths 
reduce number of necessary components
• Pair of resonance reflectors and different component
arrangement  reduced size