Cross-section diagram of DAS Mikroskop Leica OM LM 

Reflected light path i 

1 Lamphousing (12 V 100 W halogen lamp+ or Xe/Hg lamp ' ), 2 Universal reflected light 

illuminator LU +, 31ntegrated magazine for 4* filters, 4 Diffusing screen, 5 Fie ld diaphragm, 

centerable, 6 Aperture diaphragm, centerable, 7 Polarizer*, with/without A compensator, 

8 Reflectors or fluorescence filter systems (a = OF reflector*, b = BF reflector, c = Pol 

Smith reflector*), 9 Interference contrast prism*, 10 Objective nosepiece, objectives+, 

lOa Two-beam interference attachment Mireau design, lOb Two-beam interference 

attachment Michelson design, 11 Stage• with specimen, 12 Analyser*, 13 Tube lens 

system, 14 Deflecting prisms in the tube, 15 Eyepiece(s), graticule* 

Transmitted light illumination* 

16 12 V 100 W* light source, 17 Integ rateable filter, 18 Filter magazine* with 3* filter positions, 19 Field diaphragm, 20 Polarizer+*, 21 Slot for rotatable A and A/4 compensator, 

22 Condenser disc+* with interference contrast prisms*, light rings* for darkfield/ph ase 

contrast, lens*, for 2.5x objective, A and A/4 compensator*, 23 Condenser aperture 

diaphragm, 24 Condenser lenses 

+variou s possibilities; * not part of all configuratio ns 

®registered trademark 

De sign an specifications subject to alteration without notice. 

Printed in Germany 

Order nos. of the edition in: 

English Germ an Fre nch Spain 

933 765 933 764 933 766 933 768 

Part-No. 501-125 Printed in Ge rmany 08/00/GW/K H 

Leica Microsystems Wetzlar GmbH 

Ernst-Leitz-Stra 13 e 

D-35578 Wetzlar (Germany) 

Tel. +49 (0) 64 41-29 0 

Fax +49(0)6441-292255 

http:/ /www.l ei c a .com 

Brief instructions 
Fig. 1 DAS Mikroskop Leica OM LM for reflected and transm itted* light techniques 

1 Eyepiece, with adjustable eyelens*, anti-glare protection, 2 Interpupillary distance 

setting, 3 Analyser slot (reflected light), 4 Turret plate (reflectors, fluorescence filter 

systems), 5 Opening (x = recessed grip in lid for fitting reflectors, etc.), 6 Mount for IC 

prisms (interference contrast), 7 Objective nosepiece with M25 or M32 (BD) thread, 

8 Stage rotation clamp screw, 9 Condenser*, with centering screws on the left and right 

and condenser fixing screw on the right, 10 Polarizer* (transmitted light), 11 Fine focusing, (two-step* H), 12 Coarse focusing ~ Fig 2), 13 Torque adjustment coarse focus, 

14 Mains switch( ~ Fig. 2), 15 Field diaphragm*, 16 Brightness adJustment, 17 Polarizer* 

(reflected light), 18 Field diaphragm centration, 19 Fi eld diaphragm control, 20 Aperture 

diaphragm centration, 21 Aperture diaphragm control, 22 Filter magazine, 23 Clamp 

screw (stage height), 24 Stage height stop, 25 Alternating switch, reflected/transmitted 

light*, 26 Filter magazine* (transmitted light) 

*not part of all configurations 

This brief manual is a summary of the detailed German/English/French OM LM 

manual supplied with every microscope. 

The full manual also describes the assembly of the entire microscope and the 

automatic adjustment to the mains voltage in a range from. 90 V -250 V/50 - 60 Hz. 

2 

Make sure to observe the safety information in the full manual 

when changing a lamp! 

Basic brightfield setting 

Align the specimen. Release the stage height stop (1.24). Roughly adjust the 

vertical position of the microscope stage with the coarse focus (1 .12) and 

stage clamp (1.23). The position of the clamp lever (1.23) can be changed 

by pulling it vigorously outwards(= to the right) and then rotating it. Switch on 

the light source (1 .14) and switch to reflected light* (1.25) if necessary. 

Engage the BF (= brightfield) or the Smith reflector (1.4). Turn a lOx or 5x objective into the light path, switch the tube beamsplitter* to the observation position (if relevant). Remove the analyser* (1.3), polarizer* (1.17) and IC prism* 

(1.6) from the light path if present (pull out part way). Adjust lamp brightness 

( 1.16). Eyeglass wearers: Remove or turn back the a nti-g Ia re protection ( 1.1 ). 

Narrow the field diaphragm (1.19), adjust the coarse focus (1.12) until the field 

diaphragm is roughly in focus; set the torque of the coarse focusing (1.13) 

if desired. Switch the fine focusing at "fine" or "medium" by sliding the focus 

knob ( 1.11) to the left* or right. Sharply focus the specimen with the fine focus. 

Open the field diaphragm (1.19) until the whole field of view is illuminated. 

Set the eyepie ce eyelens (1.1) and the interpupillary distance (1.2). Adjust 

the contrast with the aperture diaphragm (1.21). The field diaphragm and 

aperture diaphragm can be centered according to the instructions in the full 

manual (1.18; 1.20). 

Reflected light polarization* 

First set as for brightfield (see above). Use a BF or Smith reflector. Set the 

polarizer (1.17): 

Polarizer POL*: Replug the round polarizer mount on the back so that the 

arrow H is in a horizontal position. Insert the polarizer (1.17) as far as the 

second clickstop. Slot in the analyser (1.3) and rotate until the desired 

contrast is set. 

Polarizer ICR*: Insert the polarizer so that the A engraving (lambda) points to 

the back. Push in the ana lyser (1 .3) as far as the second clickstop. Set the 

zero position (= markings coin cide). Rotate the polarizer until isotropic 

objects (mirror) appear dark. 

Polarizer with rotatable A. comprensator (not illustrated): Set the analyser at 

the zero position. Rotate the whole-wave compensator roughly th the centre 

position. Rotate the polarizer until the object is as dark or as richly contrasted 

as possible, then turn the whole-wave compensator until you achieve colour 

contrast. 

ICR reflected light interference contrast* 

Set brightfield (see above). Cross the polarizers exactly (see above), use 

PL FLUOTAR* or PL APO* objectives (use of N PLAN objectives is greatly 

restricted). Slot the objective prism (1.6) that corresponds to the code letter in 

the top line of the objective engraving (e. g. "D") above the objective nosepiece (1.6). Adjust the image contrast with the setting screw on the objective 

prism (1 .6) and adjust the aperture diaphragm (1.21 ). Colour contrast: slot in 

the polarizer with the A sign pointing to the front. 

Reflected light darkfield* 

Turn in a special darkfield objective ("BD", 1.7). Turn in the "BO" reflector 

(1.4), open the field diaphragm (1.19), set the contrast with the aperture 

diaphragm (1 .21 ). 

3 
Reflected light fluorescence* 

Use a filter system (1 .4) that is suitable for the fluorescence specimen. To 

obtain a brighter image: Screw the illumination booster (not illustrated) 

between the lamphousing and LU illuminator (not necessary for special 

fluorescence illuminator (LRF). 

Check the lamp centration* and lamp focusing*~ detailed instruction manual. 

& Danger of explosion if wrongly adjusted! 

Open the aperture diaphragm (1 .21), set the field diaphragm (1.19) to the 

diameter of the field of view (max. eyepiece field of view number= 20!), 

center if necessary (1.18; 1.20). Disengage the polarizers (1.3; 1. 17). 

Not possible for microscope models without an integrated transmitted light 

axis. 

Basic brightfield setting 

Operate mains switch (2.9) switch to transmitted light (1.25), adjust brightne ss 

(1.11); secure specimen. 

Turn in lOx objective. 

UCA/P condensers only_(.Eig,J,) and APL. ACHR . condensers 0.9 (P), 

without Fig~ 

Swing in condenser top (3.4; 3.1). Release stage height stop (1.24). Move 

stage (2.7; 1.23) and condenser (2.4) upwards. Set the turret plate* (2.15) at the 

BF = brightfield position or pull out light ring slide* (5.2). Set the field 

diaphragm (2.10) and aperture diaphragm (2.14; 3.6; 5.1) rougly at the center 

position. Focus the image with the coarse and fine focus (2.7; 2.8). An add itional focusing sensitivity* can be obtained by sliding the focus knob to the 

leftH or right (2.8). Setthe·torque for the coarse focus control if desired (2.6). 

Adjust brightness (2.11 ). 

Fig. 2 Transmitted light controls 

(for example with UCL condenser) 

1 Analyser slot (TL only) 

2 Specimen holder screw 

3 Ho le for centering key 

(UCL condenser) 

4 Condenser height adjustment 

(bi lateral controls) 

5 Settable condenser height stop 

6 Torque setting for coarse focus 

7 Coarse focusing 

8 Fine focusing (two-step* H ) 

9 Mains switch and pilot lamp 

10 Field diaphragm 

11 Brightness adjustment 

12 Mount for IC prisms and 

compensators (tube slit) 

13 Stage rotation clamp screw 

14 Aperture diaphragm 

15 Condenser turret plate*,--+ Fig. 9 

16a, b Condenser centration 

17 Stage he ight stop 

18 x, y stage adjustment 

4 

In the case of adjustable eyepieces* (1.1 ): adjust the eye lens until the edge of 

the field of view or the two images appear optimally focused. Set the interpupillary distance* on the tube (1.2). 

Koehler illumination 

Narrow (4a) the field diaphragm (1.10). Sharply focus (4b) the edge of the field 

diaphragm with the condenser height adjustment (2.4) and/or the condenser 

height stop (2.5). 

Center (4c) the image of the field diaphragm with the two centering keys 

(2.16a/b). Open the field diaphragm (2.1 0) until it just disappears from the field of 

view (4d). Adjust the aperture diaphragm (6.2; 5.1; 3.6) until you obtain optimum 

contrast. 

*not part of all configurati ons! 

One of the following contrasting techniques should be used for colourless 

specimens: 

Darkfield* DF and phase contrast* PH 

Focusing: To make it easier to find the specimen plane, pull out the light ring 

slide* (5.2) or turn the condenser turret plate* (6.3; 3.5) to the BF position and 

clo se the aperture diaphragm (3.6; 5.1; 6.2). 

Koehler illumination setting(~ p. 5 and Fig . 4). 

Open aperture diaphragm (3.6; 5.1; 6.2) fully. 

UCA and APL. ACHR. 0.9 (P) condensers only~ 

Swing in the condenser top (3.1; 3.4). 

CL/PH *,_C_LE/PH * and APL. ACHR. 0.9 (Pl condensers: 

DF: Pu sh the OF slide (5.3) into the condenser as far as the stop (5.2). 

Maximum objective aperture 0.75! 

PH: Swi ng in a phase contrast objective and slot in the corresponding light 

rin g slide (5.2 and 5.3), e. g. PH 2, as far as the stop. 

Fig. 3 UCA/P condenser Fig. 4 Setting Koehler il lumination 

Fig . 5 CL/PH or CLP/PH condenser Fig. 6 UCL/UCLP condenser 
_S_pecial OF condenser* 

----7 full manual. 

UCL*/UCLP*/UCA/P* condensers 

OF: Maximum objective aperture 0.75. Turn the condenser turret (3.5; 6.3) to 

the OF position. Insert the centering keys (3.3a/b; 6.4) into the condenser turret (3.3a/b; 6.1) at an angle from the back and adjust, with a low-magnification 

objective (4x to lOx) in the light path, until illumination or fall-off in brightness 

towards the edge is homogeneous. 

PH: Set the PH position (3.5; 6.3) corresponding to the PH objective in use, 

e. g. PH 1. 

Put an auxiliary telescope in place of an eyepiece and focus the annular 

structures (7a- c) after loosening and adjusting the front piece. Insert the 

centering keys (3.3a/b; 6.4) from the back (5.1 ), and make the images of the 

light ring LR (condenser) and the phase ring PH (objective) coincide (7c). 

Transmitted light polarisation* 

Put the analyser (8.1) into its slot. If using a rotatable analyser, turn it into the 

middle position. 

Put the polarizer (8.5a/b) into the holder (8.4) and rotate until the maximum 

extinction position is obtained without a specimen (Alternative: as in Fig. 9.8). 

Colour contrast: insert the A or A/4 compensator (8.6b) above the polarizer 

(8.6a; 9.4) and rotate. Possible alternatives: A compensator integrated in 

condenser turret and compensators for tube slit (8.8). 

Transmitted light interference contrast ICT 

Pull the objective prism (9.6) out of the light path. Turn the condenser turret 

plate (9.2) to the BF position. Insert the analyser (9.1). and set the zero position if necessary. Pull out the A compensator* (8.6b) from above the polarizer 

(9.1) if present. 

Fig. 8 Transmitted light polarization 

6 

Fig. 7 Setting phase contrast 

Fig. 9 Transmitted light interference 

contrast 

Turn the polarizer (9.9) until the maximum extinction position is reached without a specimen. Engage the condenser top (3.1; 3.4). set Koehler illumination 

----7 p. 3. 

Slide in the objective prism A, B, C, D (9.6, depending on the objective engraving). turn the condenser turret plate (9.2) to the position corresponding to the 

objective magnification (e. g. 10/20x). Adjust the contrast with the setting 

screw on the objective prism (9.6) and aperture diaphragm (9.3). 

Colour contrast: Insert A compensator (8.6b) above the polarizer (9.4) and 

rotate. 

Changing 12 V 100 W halogen lamps 

& from the mains! 

Open the right-hand side of the lamphousing with a coin. 

& Caution. hot lamp! 

Put in the replacement lamp (12 V 100 W) without tilting. 

Close the lamphousing again, reconnect to the mains. 

Centerable lamphousing only*: see full manual for centering instructions. 

Changing Hg and Xe lamps