KEYCOM provides solutions in the 300 GHz to 1 μHz frequency range (SHF/EHF/MW/UHF/VHF/ULF).
We undertake designing, manufacturing and measuring. Please feel free to contact us.

Open Resonator Method
for Sheet and Ultra Thin Sheet
Dielectric Constant and Dielectric Loss Tangent(Dk/Df)
(Millimeter Wave) Measurement System

Model No. DPS03
Highly accurate Millimeter Wave measurement ! Ideal solution for 76.5GHz, 110GHz etc. measurement !!

KEYCOM’s ultra-thin sheet measurement system employs the Fabry-Perot resonator, a linear optical resonator which consists of two highly reflecting mirrors, which combines the high measurement accuracy in the millimeter wave range and simplicity of installing the specimens.
It is also ideal for specimens with low tanδ.

・ Very accurate measurement : ex. PTFE@76.5GHz / εr' 2.05, tanδ 0.0004
・ Measurement of ultra-thin film(ex. 5μm)
・ Easy operation
・ Measurement frequency range : 18GHz-110GHz

Applicable Standard (for Sheet) :
JIS R1660-2

Publication (for thin films) :
H.Suzuki, T.Kamijo
“Millimeter wave measurement of complex permittivity by perturbation method using open resonator”
IEEE Trans. Instrument and Measurement
VOL.57. No.12, Dec.2008

Measurable Samples

PCB, Film(Ultra thin film, thin sheet), Ceramics, Radome cover, Resin etc.


Frequency 18~325GHz

Precision(repeatability) : ± 1% or ±0.01(depend on network analyzer's performance)
Precision + accuracy(to true value) (based on PTFE) : ±3% or ±0.01(depend on measurement theory and design of positioning tool)


Precision : ± 3% or ±0.0001(depend on network analyzer's performance)
Precision + accuracy(to true value) (based on PTFE) : ±7% or ±0.0001(depend on measurement theory and design of positioning tool)

Sample size

<Sample size>
・120mm x 120mm or more (18GHz)
・80mm x 80mm or more (50GHz)
<Sample thickness>
Sheet of 5μm ~ 0.2mm
or 1/2 x an integer multiple of effective wave length

Tool Size 1000mm x 400mm x 400mm
Temperature Range Room T(standard)
Please contact us for other temperature ranges

Components and parts No.

Name Specifications Model No.
Main Body Automated precision moving table
(common to all frequency ranges),
including case
Fabry-Perot resonator 18-33GHz FPR-33
26.5-40GHz FPR-40
33-50GHz FPR-50
(39-60GHz) (FPR-60)
50-75GHz FPR-75
(59-90GHz) (FPR-90)
75-110GHz FPR-110
110-125GHz FPR-125
125-140GHz FPR-140
Software (common to all frequency ranges) For sheet P118050123-01
For ultra thin sheet P118050123-02
Windows PC, Printer
GPIB interface GP-01
Network analyzer Available upon request .
Please request the model of your choice.

Measurement steps

1. Specify frequency range, frequency steps, measurement parameters(εr, tanδ, Q)
2. Name specimen, input width
3. Insert specimen
4. Start Measurement
5. Specify format of graphical output and numerical data output


Test example

Customers (Area or Country, sales)

D(Japan, US$70 billion), H(Japan, US$600 billion), T(Japan, US$20 billion), K(Japan, US$500 billion), M(Japan, US$600 billion)
ITRI(Taiwan, -), F(Asia, US$600 billion) , S(Asia, US$1 billion), H(Asia, US$800 billion), DS(Asia, US$2 billion) etc.