C12668_15 Datasheet, PDF (1/5 Pages) Hamamatsu Corporation – Balanced detectors with reduced multiple reflections flections

Balanced detectors
C12668 series
Balanced detectors with reduced multiple re-
flections
These are differential amplification type photoelectric conversion modules containing two Hamamatsu photodiodes with bal-
anced characteristics. The photodiodes are connected in a direction that cancels out the photocurrent of each photodiode.
This configuration cancels out the common mode noise of the two incident light rays. The minute difference in light levels is
treated as a displacement signal, converted into an electrical signal, and output. Moreover, the adoption of our unique struc-
ture that suppresses multiple reflections of incident light has made it possible to reduce the noise caused by the reflections.
These products can be applied to optical coherence tomography (OCT) used in ophthalmologic examinations and the like. The
balanced detector can convert into electrical signals the minute difference in the signal light produced when the back scatter-
ing light from the subject is made to interfere with the reference light.
Features
Application
Employs our unique structure that reduces multiple reflections
at the incident light wavelength of 1.0 μm or 1.3 μm
Cutoff frequency: 200 MHz
Common-mode rejection ratio (CMRR): 35 dB typ.
Input section: FC receptacle (APC polished)
A single-mode fiber with an FC connector can be connected.
Output section: SMA receptacle
Compact
OCT
Structure
Parameter
Built-in element
Dimensions
Weight
Input section
Output section
Specification
Unit
InGaAs PIN photodiode
-
65 × 75 × 25
mm
168
g
FC receptacle (APC polished)
-
SMA receptacle
-
Absolute maximum ratings
Parameter
Symbol
Condition
Value
Unit
Supply voltage
Operating temperature*¹
Vs
Ta=25 °C
Topr
±17
V
0 to +50
°C
Storage temperature*¹
Tstg
-10 to +60
°C
*1: No condensation
Note: Exceeding the absolute maximum ratings even momentarily may cause a drop in product quality. Always be sure to use the
product within the absolute maximum ratings.
www.hamamatsu.com
1