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  • Set the measurement mode to AUTO (/A/) on the setup screen.
  • Press MODE and select the R-K Mode. The following description is for when the R-K Mode selected is “R/K: Refractory/Keratometry”. The measurements made (refractometry and keratometry center measurement) differ for each R-K Mode.
  • Show the patient where to sit. Ask the patient to rest both hands on their lap and relax
  • Press the START switch on the measuring unit once an release to start measurements. Measurements will be made automatically when alignment is achieved. Repeated measurements will be made at this time. Pressing the START switch again will halt measurement. The next time the START switch is pressed measurement will resume from the point halted.

  • Roughly position the patient’s eye.

Vertical Position: Align with the vertical eye position target line.

Horizontal Position: Align with the horizontal eye position target line.

Back/Forth Direction: Position the measuring window about 40mm from the eye.

  • Running your thumb along the groove of the unit’s cover makes back/forth positioning easier. Alignment is also easier by looking through the viewfinder after lowering the forehead rest to where it just contacts the patient’s eyelashes.

NOTE: When aligning the measuring unit with the patient’s eye, take care not to tilt the unit in the vertical or horizontal plane and take care that the patient’s eyelashes do not get in the way.

  • When the position of the patient’s eye is roughly aligned during measurement, look through the viewfinder. Once the patient’s eye appears on the screen, bring the image of the pupil to the center of the screen. Next, move the measuring unit back and forth so that each dot image of mire ring can ve seen clearly.
  • Move the measuring unit close to the patient and the unit will automatically identify whether this is the left or right eye. In automatic left/right eye identification mode, a buzzer will sound during measurement to notify you that a switch has been made between the left and right eyes.

NOTE: The buzzer will sound continuously in that intermediate position between the left and right eyes where identification is uncertain.

NOTE: Sometimes it is not easy to find the eye when searching through the viewfinder and there is danger of touching the patient with the measuring unit. Be sure to roughly align the measuring unit with the patient’s line of sight before looking through the viewfinder.

NOTE: The buzzer sound that occurs in automatic left/right eye identification mode will go off even if the initial setting for BUZZER on the SETUP screen is set to OFF.

  • Measurements will be made automatically when alignment is achieved. The buzzer will sound each time a measurement is made. A short beep will sound keratometry and a long beep will sound for refractometry. During measurement, dour light spots will appear for keratometry, while a central light spot will appear to refractometry. This operation will be repeated in refractometry/keratometry ,ode. During measurement, an auto fogging mechanism will activate. This makes the target slightly blurry.
  • Measurement results are displayed on the screen.
  • When making further measurements, measurement will automatically end and the figure at right will appear on the monitor screen (The figure is a sample of what appears after measurement of the right eye). Press the START switch at the time to measure the right eye again.

  • Perform the same procedure to measure the other eye.
  • Once measurements for both eyes are finished, aim the front panel of the measuring unit at the printer and press the PRINT key. After printing, representative values will appear inside the viewfinder. Go to Step 4 and repeat to continue with more measurements. If no more measurements are needed, perform Steps 12 and Steps 13.
  • Retract the forehead rest if you were using it.
  • Turn off the measuring unit’s power switch. Placing the measuring unit in its place on the station will also result in power being turned off automatically.
  • Return the measuring unit to its place on the station.
  • The following figures show sample screens for refractometry mode and keratometry mode.

  • IF there is any foreign matter (such as opacity in the crystalline lens caused by cataracts, other opacity or scratches) obstructing the light from entering the pupil during measurement, it will appear as a black shadow. If there are any black shadows, observe the pupil in retro illumination mode and proceed with further examination of the eye using the slight lamp.
  • Set the measurement mode to CONTINUOUS (/C/) on the setup screen
  • Press MODE and select the R-K mode.
  • Measure the patient’s eye using the same steps throughin Auto Measurement Mode section.


In this mode, measurement does not end automatically, rather it is continuous.

Be sure to measure each eye at least five times.

Increase the number of measurement even more if there are fluctuations in the measured values or lots of eye movement.

Up to eight refractometry and keratometry results can be stored per eye.

  • Press the START switch when you want to end measurement for given eye. (The measurement will stop temporarily). Or switch left/right eye measurement in the middle of measurement.
  • Measure the other eye the same way.
  • Press the PRINT key when you want to print out the measurement results.


Quick mode, with shortened refractometry times, is useful such as when measurement is difficult due to quick motion of the eye in the case of an infant or nystagmus.


Although the refractometry time in Quick Mode is reduced to about half of the usual time, fluctuations is measured values may increas

The length of time required for keratometry does not change in Quick Mode.

Do not use this mode under normal conditions.

A “Q” is printed on the print paper to indicate quick mode.

  • Press QUICK and set the measurement mode to Q.
  • Position the measuring head versus the patient’s eye using the same Step 3 through Step 9 as given in the Auto Measurement Mode Section.


In this mode, measurement does not stop automatically. Measurement is continuous.

Be sure to take refractometry for each eye at least five times.

The measurement count can be increased even further if the eye moves a lot or if there are fluctuations in the measured values;.

Up to eight refractometry and keratometry results can be stored per eye.

  • Press the measurement switch to end measurement for a given eye. (The measurement will stop temporarily). Or switch left/right eye measurement in the middle of measurement.
  • Measure the other eye in the same way.
  • Press the PRINT key when you want to print out the measurement results.
  • Press the PERI key. The unit will enter cornea periphery keratometry mode and the screen will change.
  • Roughly align the mire ring and alignment marks and press the START switch (This is the same procedure as used for normal keratometry). Light spots will flash and measurement will repeat. Measurement of the central area and horizontal peripheral area will be performed alternately.
  • After repeating measurements several times, press the START switch. The measurement will end and the cursor will move to the bottom. Peripheral measurement in the horizontal direction will end. If measurements in the vertical direction are unnecessary. Press the PRINT key and print out the data. When printout is selected, refractometry values, keratometry values, and cornea periphery values, will be printed. If vertical measurement are also to be performed, proceed to the next measurement without pressing the PRINT key.

Vertical Measurement

  • Rotated the measuring unit 90° (in the same direction shown in the figure). Check that the cursor is as shown in the figure at the right and that the upper direction mark appears at the top.
  • Perform measurement. Measurement is made in the same way as for the horizontal direction.
  • Measure several times and then 0press the PRINT key.


During peripheral measurements, right/left eye identification must be performed manually.

Do not use the forehead rest when measuring in the vertical direction as it may strike the patient in the other eye.

Measurements may be impossible due to the patient’s eyelids for eyelashes obstructing the measuring beam during measurements in the vertical direction. If this happens, have the patient open their eyes as widely as possible and try measuring again.