LEP discussion thread: (White laser flashlights)

lumen aeternum

Sep 29, 2012
Toys received in the mail: Transmissive White Phosphor Plates.

I confirmed them to be transmissive and to produce a very bright white appearing output. Great they used Sapphire for the wafer as it will conduct heat well when mounted to a heat sink. Maximum pump power from the laser is 7 watts per square mm.

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These plates are very small, three sizes listed at the below link:

From smallest to largest:

1. Three mm diameter sapphire wafer with 1 mm phosphor spot (measured .65 mm spot) 5700K $30.00

2. Five mm diameter sapphire wafer with 1 mm spot (measured .65 mm spot) 6000K $30.00

3. Eight mm diameter sapphire wafer with 3 mm spot (measured 3 mm spot) 7000K $30.00

Excitation Wavelength440-460nm
Phosphor Dimensions (The yellow area)φ3mm/φ1mm
Total Dimensionsφ8*0.7mm/φ5*0.65mm/φ3*0.65mm
Base Plate MaterialSapphire
Color Temperature5700K / 6000K / 7000K
Light Efficiency (Laser to White Light)165lm/[email protected]
Max Working Temperature200℃
Max Laser Power Density7W/mm^2

View attachment 27916

Thermal conductivity of Sapphire:

Nonmetals are often thought of as being relatively poor conductors of heat; however crystalline nonmetals can actually have very high thermal conductivities. The thermal conductivity of sapphire (aluminum oxide) actually exceeds that of very pure copper (RRR 500), from about 20K to 100K. Sapphire is used as an electrical insulator in heat sinking applications (magnet leads, for example) where excellent thermal conductivity and electrical isolation are required.

View attachment 27917
Note: 375 K is close to 100 C., 475 K is close to 200 C.

Shenzhen Guangchuangfeng Technology Co., Ltd.Contact Name: Sabrina Zhao

Registered company address: CN, Guangdong, Shenzhen, B1607, Rongde Times Square, Huaqiao New Village Community, Henggang Street, Longgang District Company Tel: 86-0755-13128736762
Company Email: [email protected]
Link on that page for a module containing laser & wafer, just add power for $70