Glass-to-Metal Seals

Glass-to-Metal Seals


A glass-to-metal seal, is characterized by its hermeticity and superior electrical characteristics. It is used widely in areas such as laser diodes and sensors for in-car use, where reliability is an important factor.
At SHINKO, we offer not just the industry standard for laser diodes for optical pickups, the ø5.6mm-type, but also caps with stems or window-glass, depending on the needs of customers.
As we react flexibly to diversifying customer needs, we are able to carry out all the integrated production processes (from product design, mold design, stamping, to plating), based on a thorough quality management regime.


  • A package, made of metal and glass, with superior electrical characteristics and hermeticity
  • Optimum for laser diodes, on-board sensors, and other devices where high reliability is vital


  • Extremely airtight (compression type:1x10-9 Pa m3/sec and lower)
  • High thermal conduction properties (Fe/Cu/Fe clad type and copper-block type)


  • Two types of structures, the 'matched type' and the 'compression type',depending on the type of glass sealing used


  • Material List

Header : Matched Type

No. Parts Material Thermal expansion ratio (α)
1 Eyelet Kovar 48×10-7/°C
2.3 Lead Kovar 48×10-7/°C
4 Glass Tablet Hard glass 48×10-7/°C

(α = Average of temp.from 30°C to 450°C)

Header : Compression Type

No. Parts Material Thermal expansion ratio (α)
1 Eyelet Steel 150×10-7/℃
2.3 Lead 50%Ni-Fe 97×10-7/℃
4 Glass Tablet Soft glass 97×10-7/℃

(α = Average of temp.from 30°C to 450°C )

Cap ( Pb Free )

No. Parts Material
1 Eyelet Ni-Fe
2 Window Clear glass
3 Adhesion Low temperature glass (Pb Free)


  • In laser diodes[LD](optical pickups and optical communications devices)
  • In sensors for automobiles
  • In transistors , ICs and LEDs

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