Balanced detectors C12668 series Balanced detectors with reduced multiple reflections These are differential amplification type photoelectric conversion modules containing two Hamamatsu photodiodes with balanced 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 structure 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 scattering 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 OCT 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 Structure Parameter Built-in element Dimensions Weight Input section Output section Specification InGaAs PIN photodiode 65 × 75 × 25 168 FC receptacle (APC polished) SMA receptacle Unit mm g - Absolute maximum ratings Parameter Supply voltage Operating temperature*1 Storage temperature*1 Symbol Vs Topr Tstg Condition Ta=25 °C Value ±17 0 to +50 -10 to +60 Unit V °C °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 Balanced detectors C12668 series Electrical characteristics (Ta=25 °C, unless otherwise noted) Parameter Supply voltage*2 Current consumption Symbol Vs Ic Output impedance Zo Condition ±12 V ±12 V, dark state OUT terminal Monitor terminal Min. ±11 ±52 - Typ. ±12 ±60 50 220 Max. ±13 ±64 - Unit V mA Ω *2: Use a power supply with at least 200 mA output. Electrical and optical characteristics (Typ. Ta=25 °C, unless otherwise noted) Parameter Optimal wavelength band*3 Photosensitivity Symbol λo SPD Frequency bandwidth fb CMRR Common-mode rejection ratio*4 Transimpedance gain Zt Output noise voltage Vn Condition Optimal wavelength -3 dB, OUT terminal -3 dB, Monitor terminal OUT terminal OUT terminal Monitor terminal Dark state, 50 Ω termination, OUT terminal C12668-01 1.0 0.75 C12668-02 1.3 0.95 DC to 200 DC to 0.1 35 3 × 104 1 × 104 40 max. Unit μm A/W MHz dB V/A V/A mVp-p *3: Wavelength band in which multiple reflections can be reduced the most *4: Output difference when an approximately 70 μW light is applied to only the INPUT- terminal and when applied to INPUT+ and INPUT- terminals (see the frequency characteristics) Frequency characteristics (typical example) (Ta=25 °C) 60 50 Output (dB) 40 Applied only to INPUT- terminal Applied to INPUT+ and INPUT- terminals 30 CMRR 20 10 0 -10 0.01 0.1 1 10 100 1000 Frequency (MHz) KACCB0358EA 2 Balanced detectors C12668 series Block diagram Amplifier Mon- INPUT- Amplifier I/V amplifier OUT INPUT+ Amplifier Mon+ KACCC0761EA Dimensional outline (unit: mm) 54.5 (15) P.S. ±12 V (9.5) (14) Mon.- INPUT(FC/APC) (28.5) 65 OUT (15) INPUT+ (FC/APC) (20) (10.5) Mon.+ (7.5) (11) (8.5) (11) M4 indication 10 M4 depth 6 11 (24) 14 No8-32UNC depth 6 Tolerance unless otherwise noted: ±0.3 KACCA0351EA 3 Balanced detectors C12668 series Accessory (unit: mm) Cable for power supply (no connector on one end) 4 (ɸ9.8) 3 RKMV 3-224/2M (LUMBERG AUTOMATION, 3-pin, female) (8.2) (27) Pin no. 1 3 4 (15) (4.3) 1 (2000) Wire color Brown (+12 V) Blue (-12 V) Black (GND) KACCA0352EA Connection example (ophthalmic medical OCT) OCT Mirror for reference light Wavelength swept light source Eyeball Interference light DAQ interface + PC Balanced Balanced dd detector KACCC0762EA 4 Balanced detector C12668 series Related information www.hamamatsu.com/sp/ssd/doc_en.html Precautions · Disclaimer Information described in this material is current as of February, 2015. Product specifications are subject to change without prior notice due to improvements or other reasons. This document has been carefully prepared and the information contained is believed to be accurate. In rare cases, however, there may be inaccuracies such as text errors. Before using these products, always contact us for the delivery specification sheet to check the latest specifications. The product warranty is valid for one year after delivery and is limited to product repair or replacement for defects discovered and reported to us within that one year period. However, even if within the warranty period we accept absolutely no liability for any loss caused by natural disasters or improper product use. Copying or reprinting the contents described in this material in whole or in part is prohibited without our prior permission. www.hamamatsu.com HAMAMATSU PHOTONICS K.K., Solid State Division 1126-1 Ichino-cho, Higashi-ku, Hamamatsu City, 435-8558 Japan, Telephone: (81) 53-434-3311, Fax: (81) 53-434-5184 U.S.A.: Hamamatsu Corporation: 360 Foothill Road, Bridgewater, N.J. 08807, U.S.A., Telephone: (1) 908-231-0960, Fax: (1) 908-231-1218 Germany: Hamamatsu Photonics Deutschland GmbH: Arzbergerstr. 10, D-82211 Herrsching am Ammersee, Germany, Telephone: (49) 8152-375-0, Fax: (49) 8152-265-8 France: Hamamatsu Photonics France S.A.R.L.: 19, Rue du Saule Trapu, Parc du Moulin de Massy, 91882 Massy Cedex, France, Telephone: 33-(1) 69 53 71 00, Fax: 33-(1) 69 53 71 10 United Kingdom: Hamamatsu Photonics UK Limited: 2 Howard Court, 10 Tewin Road, Welwyn Garden City, Hertfordshire AL7 1BW, United Kingdom, Telephone: (44) 1707-294888, Fax: (44) 1707-325777 North Europe: Hamamatsu Photonics Norden AB: Torshamnsgatan 35 16440 Kista, Sweden, Telephone: (46) 8-509-031-00, Fax: (46) 8-509-031-01 Italy: Hamamatsu Photonics Italia S.r.l.: Strada della Moia, 1 int. 6, 20020 Arese (Milano), Italy, Telephone: (39) 02-93581733, Fax: (39) 02-93581741 China: Hamamatsu Photonics (China) Co., Ltd.: B1201, Jiaming Center, No.27 Dongsanhuan Beilu, Chaoyang District, Beijing 100020, China, Telephone: (86) 10-6586-6006, Fax: (86) 10-6586-2866 Cat. No. KACC1219E01 Feb. 2015 DN 5