Quantum Instruments Cascade Laser Starter Kit manual

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  • Página 1

    Quan tum Cascade Las er Starter Kit Instructio ns Man ual (W eb v ers ion) CA UTION Before using the Qua nt um Cascade Laser Starter Kit, rea d this do cument ation and take sp ecial note of all s afety instructions[...]

  • Página 2

    Con ten ts 1 Iden tification 4 1.1 Doc umen t . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1.2 Limited waran ty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 General 5 2.1 Chapter ov erview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

  • Página 3

    2 4.6.5 Laser peak voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.6.6 Av era ge dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.6.7 Accuracy considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 4.7 QCL pulser timing unit ( TPG12 8) . . . . [...]

  • Página 4

    3 10 App endix 55 10.1 Bias Circut (”Bias-T”) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.2 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 10.1.3 Specifica[...]

  • Página 5

    Chapter 1 Iden tification 1.1 Do cumen t Quantum Cascade Laser Starter Kit Instructions Manual. W e b V ersion 3.1 0 2.07 Man ufacturer Alpes La sers SA 1-3 P assa ge Max-Meuro n CP 1766 CH-2001 Neuchˆ a tel T el. ++41 32 7299 510 F ax. ++41 32 72 13619 h ttp://www.alp esla sers.ch info@alp eslaser s.ch 1.2 Limited w aran t y Alpes Lasers SA will[...]

  • Página 6

    Chapter 2 General 2.1 Chapter o v erview This chapter giv es basic information o n system func- tions, sp ecifications and do cumentation. 2.2 Generalit ies The indications in the present Instructions Manual, in par ticular the safety instructions must be co m- plied with. 2.3 Compliance The Q uantum Cascade Laser Starter Kit has b een designed to[...]

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    Starter Kit Instruction Manual General 6 2.4 Glossary The following terms, among others , are used in this Instructions Manual. 2.4.1 P ersons P ersonnel Personnel refers to all p ersons who carr y out any activit y with the instrumentation and meet the manuf acturer’s requirements about p ersonnel to run those activities and have been therefore [...]

  • Página 8

    Starter Kit Instruction Manual General 7 2.5 T yp ographic con v en tions The following st yles a re used in this manual. Description st yle This st yle, used in relation with a num ber in il- lustrations (figures) is preceded by the corresp ond- ing n umber: Example: (1) First item. (2) Second item. (3) etc... Commands st yle All so ft ware comma[...]

  • Página 9

    Starter Kit Instruction Manual General 8 Pro cedure effects sty le The pro cedur e effects are descr ib ed by using the following sym b ol , → . Example: [1] Click on the Delete Sample icon. , → The messag e Do you r e al ly want to delete the sample ? app ea rs. Cross references sty le This style is used to help the p ers onnel to find othe[...]

  • Página 10

    Starter Kit Instruction Manual General 9 Note st yle Used when the p ersonnel a tten tion must be drawn to a par ticular op era tion or information. Example: Note: The lab or atory housing LLH100 makes availa ble two outputs giving ac c ess t o these voltage. Caution st yle Used to preven t the p erso nnel from any danger or hazardous situation. No[...]

  • Página 11

    Chapter 3 Safet y Instructions 3.1 Chapter o v erview This chapter sets out safety instructions for ensur- ing safe and trouble- free oper ation of the s ystem describ ed in this manual. 3.2 In tro duction 3.2.1 Principle The p er sonnel must hav e read and understo od this do cument ation befor e car rying out a ny activit y what- so ever with the[...]

  • Página 12

    Starter Kit Instruction Manual Safet y Instructions 11 3.3 General safet y instructions • Never attemp t to use a system for purpose s other than those detailed in this manual. • Never attemp t to use a sy stem in conjunc- tion with o ther instruments without obtain- ing prior information and approv al from the manuf acturer. • Never attempt [...]

  • Página 13

    Chapter 4 Description 4.1 Chapter o v erview This chapter gives a basic descr iption of the Qua n- tum Casca de Laser Star ter Kit system a nd its com- po sition. 4.2 System Comp osition The Quantum Cascade Laser Starter Kit is made up of the following items: (1) La b orator y Laser Housing (LLH10 0) (2) T emperatur e Controller (TCU151) (3) QCL pu[...]

  • Página 14

    Starter Kit Instruction Manual Description 13 4.3 DFB and F P Quan tum Cascade Lasers 4.3.1 Description Quantum Cascade La sers (QCL) are unip olar las ers emitting in the mid-infrared from 4 to 17 microns. The laser is a ridge of InGaAs and AlInAs grown on InP providing ga in and a F abry-Perot cavit y in order to build the las er o scillation up.[...]

  • Página 15

    Starter Kit Instruction Manual Description 14 4.3.3 Sp ecifications F ar field elliptical (FWHM): V ertical: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 ◦ Horizontal: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

  • Página 16

    Starter Kit Instruction Manual Description 15 4.3.4 Electrical mo del The QCL can be mo delised in a R C circuit. Electrical m o del cha racteristics The v a lues given below apply for a 1 0 µ m laser wa velength. Note: V oltag e and r esistor values may vary ac c or ding t o the typ e of laser. R1 : . . . . . . . . . . . . . . . . . . . . . . . .[...]

  • Página 17

    Starter Kit Instruction Manual Description 16 4.4 Lab oratory Laser Housing(LLH100) 4.4.1 Description The Lab ora tory Laser Housing is a Ther mo-Electric co oled b ox which encapsulates the Quantum Cas- cade Laser. The internal tempera ture is co n trolled by a PT- 100 sensor a nd heat is dissipa ted by air or water. The LLH10 0 is des igned to ea[...]

  • Página 18

    Starter Kit Instruction Manual Description 17 LLH100 in ternal view The La b orator y Laser Housing includes the follow- ing items: (1) LLH100 to p cov er (2) PET U-sha ped holder (3) Gilded copper contact (U P a nd DN) (4) Laser (5) Laser r eceptacle 4.4.2 Sp ecifications Maximum P eltier current (with water co oling): . . . . . . . . . . . . . .[...]

  • Página 19

    Starter Kit Instruction Manual Description 18 4.4.3 Thermo-Electric Co oler (TE C) and PT100 connections The pin 1 is recog nised b y a circle around it and a thin no on ended circle star ts from pin one and turns around the pins until pin 6. (1) Pin 1: + Peltier elemen t (2) Pin 2 : - Peltier element (3) Pin 3 : I+ P T100 (4) Pin 4 : Sens + P T100[...]

  • Página 20

    Starter Kit Instruction Manual Description 19 4.4.4 Measuremen t connection These connections give access to the voltage on the laser. The ”L” connection is connected AC coupled to the catho de o f the las er through a divider by ten. The end o f cable must be 5 0Ω terminated for accu- rate measurement. The ”B” is connected the sa me to t[...]

  • Página 21

    Starter Kit Instruction Manual Description 20 4.5 QCL pulser switc hing un it(LDD100) 4.5.1 Description The switchin g unit is ba sed on dedicated p ower MOS-FETS with up to 30A current compatibilities and 60V. In addition, the circuit is limited in p ow er dissipation b y the coo ling of the u nit. During op- eration, the tempera ture of the case [...]

  • Página 22

    Starter Kit Instruction Manual Description 21 4.6 QCL pulse switc hing measuring unit 4.6.1 Generalities The meas uring circuit co ntained in the LDD100 provides information ab o ut v arious laser pulse pa- rameters (pea k voltages, supply v oltage s, dut y cy- cle, frequency). They are only estimated v alues, since exa ct measurement of short a nd[...]

  • Página 23

    Starter Kit Instruction Manual Description 22 Dut y cycle calculation UPI can b e use d to calculate the duty factor as follows: d f = 2 U P I − ν P low ν P hig h − ν P low with v P low and v P hig h as ab ove. T o get the real duty cycle, df must be corr ected as follows: dc = f LDD d f = f LDD 2 U P I − ν P low ν P high − ν P low to[...]

  • Página 24

    Starter Kit Instruction Manual Description 23 4.6.5 Laser p eak v oltage The la ser p eak voltage is given by: U peak = 2 U LH − U LL peak where U LL peak is the co rrected p eak v alue o f ULL a s calculated in the previo us paragr aph. 4.6.6 Av erage dissipation The average thermal diss ipation o f the lase r is given b y: P = U peak I peak d c[...]

  • Página 25

    Starter Kit Instruction Manual Description 24 4.7 QCL pulser timing unit (TPG128) 4.7.1 Description The QCL pulser timing unit is designed to control the QCL pulser switching unit. It provides TTL pulses on 5 0Ω on tw o indep en- den t outputs. The pulse dura tion is adjustable from 0 to 200 ns. The interv al be t ween pulses can be a d- justed b[...]

  • Página 26

    Starter Kit Instruction Manual Description 25 4.8 QCL temp erature con troller(TCU151 ) 4.8.1 Description The TCU15 1 is used to c ontrol the laser ’s temper - ature inside the Lab ora tory Laser Ho using. It uses a P T100 senso r to measure the tempe ra- ture of the cold plate and maintains a pre-set tem- per ature either fro m a front panel kno[...]

  • Página 27

    Chapter 5 Installation 5.1 Chapter o v erview This chapter des crib es the installation and the con- nection of the QCL Star ter Kit. It a lso explains the op erating chec ks b efor e the normal use. 5.2 General The setup pro cedures outlined below must b e fol- low ed meticulously to ensure that QCL Starter K it op erates cor rectly and safely . 5[...]

  • Página 28

    Starter Kit Instruction Manual Installation 27 5.4 Setting the appropriate A C v oltage on TCU151 The TCU15 1 temperature controller w orks on 110 /120 V or 2 20/2 40V if the fuse ho lder is o riented in the ap- propriate p osition. Note: Th er e ar e two r ates: 110-120 V, 60Hz (USA) 220-240 V, 50Hz (Eur op e) 5.4.1 Pro cedure T o set the appropr [...]

  • Página 29

    Starter Kit Instruction Manual Installation 28 5.5 Installing the starter Kit 5.5.1 Before b eginning Make sure that the fo llowing devices are tur ned OFF: • TPG128 • TCU151 • User DC p ow er supply 5.5.2 Pro cedure T o install the QCL Starter Kit, pr o ceed as follows: [1] Plug t he low im p edance line in to the LLH100 connector (2). The l[...]

  • Página 30

    Starter Kit Instruction Manual Installation 29 [3] Plug the cable ( 3) onto the LDD100(4). [4] Plug the +12VDC co nnector (1) in to the TPG128 (9). [5] Plug the trigger BNC co nnector (2) in to the TPG1 28 (9) Out 1 o r Out 2 o utptut. CAUTION ! The u nit must b e flo ating. [6] Plug the banana cables (8) (red and black) in to the DC p ow er suppl[...]

  • Página 31

    Chapter 6 Use 6.1 Chapter o v erview This chapter describ es how to use the QCL Sta rter Kit. It also explains the functionalities o f the TPG1 28 and the T emp erature Controller (TCU151). 6.2 QCL pulse timing unit com- mand description The Quantum Cascade La ser is con trolled by the QCL pulse timing unit TPG1 28. The TPG12 8 front panel is comp [...]

  • Página 32

    Starter Kit Instruction Manual Use 31 6.3 TCU151 command description The in ternal temp erature o f the LLH100 is driven b y the TCU15 1 unit. The T empe rature Co nt roler fro nt and rear pan- els are co mpo sed of the following items: (1) Set T emperature 5 turns p otentiometer: Allows to set the internal temper ature refer- ence. (2) LCD 3 dig i[...]

  • Página 33

    Starter Kit Instruction Manual Use 32 6.4 Laser utilisa tion 6.4.1 Ov er view In order to insure a cor rect use and and an appropri- ate lifetime to the laser, it is r ecommended to pro- ceed accor ding a s pec ific order as b elow: • Start water flo w to co ol the LLH1 00. • T urn on the temperature controller and set the desired temp eratur[...]

  • Página 34

    Starter Kit Instruction Manual Use 33 [5] T urn the TPG128 ON (8) and set the pu lse per io d to 2.0 and the range to 0.5 to 10.5 µ s (medium), cor resp onding to a perio d length of ab out 2.5 us, or to t he v a lues sp ecified on the datashee t or by Alpes La sers. [6] Set the pulse duration (11 ) to 3.0, corr e- sp onding to a pulse length of [...]

  • Página 35

    Starter Kit Instruction Manual Use 34 6.5 In terlo c k utilisation The tempe rature co nt roller is designed with an built- in in terlo ck (1). This function is activ ated when a fault o ccur s on the TCU151 controller (ov er-temp erature, ov er-current, etc.). The in terlo ck is b y default a NC (Normally Clos e) relay con tact. CAUTION ! It is al[...]

  • Página 36

    Chapter 7 T roublesho oting 7.1 Chapter o v erview This chapter sets out troublesho oting instructions for ensur ing sa fe and tro uble-free o p eration of the Quantum Cascade Laser Starter Kit sys tem. 7.2 Principle The p er sonnel must hav e read and understo o d this do cument ation befor e car rying out a ny activit y what- so ever with the Q u[...]

  • Página 37

    Starter Kit Instruction Manual T roublesho oting 36 Laser dra ws curren t but giv es no ligh t - The laser ma y b e rev erse d p olarized (it is not a desirable situation but do es gen- erally not de stro y the laser). √ Check t he p ola rity of the connection. - The p ol arit y is right . It dra ws to o muc h curren t and the p o w er meter is m[...]

  • Página 38

    Chapter 8 Main tenance 8.1 Ov erview This chapter describes a ll pro cedur es of mainte- nance and ca libration for the QCL s tarter K it. The pro cedures descr ibed herein must be p erfor med by per sonnel trained on the electronic field, with ac- ceptance by Alp es Lasers, otherwise the w arr ant y will be lo st. Note: The TTL Pulse Gener ator ([...]

  • Página 39

    Starter Kit Instruction Manual Maint enance 38 8.2 Replacemen t pro cedures 8.2.1 Quan tum Cascade Laser replace- men t Before b eginni ng [1] Switch the QCL Starter Kit OFF Material needed • 1 set of Allen keys. • 1 ohmmeter. • 1 QCL laser . • a pair o f tw eez ers. Pro cedure T o replace the Q uantu m Ca scade Laser , pro ceed a s follows[...]

  • Página 40

    Starter Kit Instruction Manual Maint enance 39 [4] Install the new laser ( 4) into the holder using small tw eeze rs ( 0 .5cm ap er ture). [5] Hold the laser (4) o n the g ilded ceramic pads with the tw eezers pins along the axis o f the largest length o f the copper submount. [6] Pla ce it in the receptacle pa rallel to the window. ! W arning ! Av[...]

  • Página 41

    Starter Kit Instruction Manual Maint enance 40 8.2.2 QCL ”UP” and ”D N” p osition exc hange Before b eginni ng [1] Switch the QCL Starter Kit OFF. Material needed • 1 set of Allen keys. • 1 ohmmeter. • 1 FP-Q CL laser contact plate. • 1 pair o f tw eez ers. Pro cedure T o exchange the b eam of a Quantum Cascade Las er, pro ceed as f[...]

  • Página 42

    Starter Kit Instruction Manual Maint enance 41 [5] Place the screws (3) in the PE T holder (4). [6] Place the PET holder (4) on the t wo guides (5) on the bac k of the laser receptacle ( 6) being ca reful of maintaining the PET holder higher on the laser side than on the back side. [7] Once the holder (4) is eng aged in the guides, push it down unt[...]

  • Página 43

    Starter Kit Instruction Manual Maint enance 42 8.3 TCU151 temp erature con- troller in terlo ck se tting 8.3.1 Generalities The interlock is lo cated on the main b oard. Note: By default, the interlo ck is set t o NC (Nor- mal ly Close) c ont act. 8.3.2 Before b eggining in terlo ck set- ting [1] Switch the instrument OFF. [2] Unplug the p ow er co[...]

  • Página 44

    Starter Kit Instruction Manual Maint enance 43 8.4 Calibarati on pro cedures 8.4.1 TPG128 calibration Generalities The present section descr ib es pro ce dure to b e ca r- ried out for pa rticular calibration of the TPG128 . Before b eginni ng [1] Switch the instrument OFF. [2] Remov e the cov er (1). [3] Switch the instrument ON. ! W ARNING ! Keep[...]

  • Página 45

    Starter Kit Instruction Manual Maint enance 44 [5] Cho os e the ra nge 5 µ s to 1 05 µ s. Pot 10 turns Perio d on 10 . Adjust the adjustable capacitor max 105 µ s adj (4) in order to obtain a 105 µ s lo ng per io d. [6] Pot 10 turns Perio d on 0. Ajust the p ot Perio d min adj (1) in or der to ha ve a p erio d of 5 µ s. [7] Repea t steps 5) an[...]

  • Página 46

    Starter Kit Instruction Manual Maint enance 45 [12] Connect o scilloscop e o n the output Ou t1 . Load with a 50Ω . Choose a rep etition p erio d of ab out 5 µ s. [13] Pot 10 turns Dur ation on 10. Adjust capacitor Max dur ation (2) to hav e a output pulse of 200 ns + /-5 ns. [14] Pot 10 turns Du r ation o n 0. Adjust the po t Out 0ns adj (1) in[...]

  • Página 47

    Starter Kit Instruction Manual Maint enance 46 8.4.2 TCU151 temp erature controller calibration ! W ARNING ! Keep in mind that during the calibration pro cedure, the instrument is p ow ered on. Before b eginni ng [1] Po wer off the instrument. [2] Op en the TCU151 top cover (1) to a ccess the TCU151 ma in b oard (2). Material needed • V oltmeter[...]

  • Página 48

    Starter Kit Instruction Manual Maint enance 47 Sensing level and range adjustemen t [4] Replace the ca ble connected to J 8 (4) with the 100Ω 1% refere nce resistor in the follow- ing w ay: Connect one side of the resis tors to pins 1 and 2, the other side to pins 3 and 4. [5] Measur e the voltage on Zn3/R10 (3). Note: Th e value should b e: - V [...]

  • Página 49

    Starter Kit Instruction Manual Maint enance 48 T emp erature Reference offset adjustment [10] Adjust B13 (3) to 0.000 with P3 (4) [11] Set the temp era ture with the Set T em- p er atur e p otentiometer (Fig.40 (7)) to +5 ◦ C , → The temp erature reference signa l B13 s hould be ≥ 4 .3V [12] Set the temp era ture with the Set T em- p er atur[...]

  • Página 50

    Starter Kit Instruction Manual Maint enance 49 Oscillator c hec k [15] Measure the fre quency on the pin 7 of U13 (1). Note: Th e value is 28KHz + /- 3KHz Curren t/V oltage ratio adjustment [16] Adjust the trimmer P4 (6) in order to read B4 = 0 .6V (4). [17] Set the selector (5) to mo de Setting +I . The LCD scr e en should display 1.00 A . Note: I[...]

  • Página 51

    Starter Kit Instruction Manual Maint enance 50 CA UTION ! F or the further steps of this c hec k, li mit the pos itiv e cur ren t to 1 A and the negativ e one with 1.2 A b y means of the 5 turns p oten tiome ter) T emp erature lim it threshold [21] Measure the voltage on pi n 2 o f U10 (1). Note: The value should b e: 0.7V (= 70 ◦ C) (If ne e de [...]

  • Página 52

    Starter Kit Instruction Manual Maint enance 51 Curren t adjustmen t [28] Set the selec tor (3) to mo de Setting ◦ C and adjust the temper ature v a lue to 25 ◦ C b y means of the Set T emp er atur e 5 tuns po rtentiometer P8 (2). [29] On the external p ower supply , rise slowly the v oltage to 30 V a nd the current to 1.5 A. , → The tension s[...]

  • Página 53

    Starter Kit Instruction Manual Maint enance 52 Miscellaneous functions testing T emp erature limit tes ting [37] Decre ase the temper ature limit threshold from 0.7 V to 0.3 V. Note: F or mor e details, se e T emp er atur e limit thr eshold on p age 50. [38] Increase the temperature refer ence to 35 ◦ C. , → When the thr eshold is overp asse d,[...]

  • Página 54

    Chapter 9 Application notes 9.1 Detection t ec hniques 9.1.1 Direct absorption In a direct a bsorption meas urement, the change in in tensity of a b eam is reco rded as the la tter crosse s a sa mpling cell wher e the chemical to b e detected is contained. This measurement tec hnique has the adv antage of simplicit y . In a version of this techniqu[...]

  • Página 55

    Starter Kit Instruction Manual Maint enance 54 9.1.3 Photoacoustic detection In the photoacoustic detection, the optica l b eam is per io dically mo dulated in amplitude b efore illumi- nating the cell containing the absorbing c hemical. The expansio n generated by the p erio dic heating of the c hemical crea tes an aco ustic wa ve whic h is detect[...]

  • Página 56

    Chapter 10 App endix 10.1 Bias Circut (”Bias-T”) 10.1.1 General The Bia s-T a llows to apply a constan t (DC) cur - rent to the laser in addition to the pulsed current (therefore a Bias -T is useless in CW mo de). The current is drawn from the externa l (user supplied) power supply through the laser. This curr ent can be co nt rolled electr ica[...]

  • Página 57

    Starter Kit Instruction Manual Appendix 56 10.1.3 Spec ifications Bias frequency . . . . . . . . . . . . . . . . Up to 100 Hz Ac hiev a ble shift . . . . . . . . . . . . . . . . . . . . . . . . 0.1% Input voltage U in . . . . . . . . . . . . . . . . . . . 0 to 3 V Input voltage threshold . . . . . . . . . . . . . . . . 0.6 V Input frequency F in .[...]

  • Página 58

    Starter Kit Instruction Manual Appendix 57 Dangers and di sadv an tages of usi ng a Bias- T circuit • Since a Bias-T only allows to heat the laser, the emiss ion wa velength can only b e increased (or emission wa ven umber decrea sed), a nd out- put p ow er will decrease with increased Bias current, due to the additional heating. This means that [...]

  • Página 59

    Starter Kit Instruction Manual Appendix 58 • As a rule of thum b, the ov erall dissipated power (sum of DC Bias current dissipation and pulse current dissipation) must never be higher than the average dissipated p ower given by the high- est current / voltage / tempe rature combina- tion sp ecified in the data sheet. T ak e into account that the[...]

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    Starter Kit Instruction Manual Appendix 59 10.2 Unpac king NS laser from its transp ortation b o x Fig.54: Unpack ing instructions for NS s ubmoun ts[...]