1. OPTOMETRIC EQUIPMENTS IN REFRACTION ROOM
Presented by
T.Muthuramalingam

2. Contents RAF Ruler JCC Illuminated bulb Autorefractometer Mirror PC
Torch
Retinoscope
Trial set
Trial frame
JCC
Autorefractometer
RAF Ruler
Prism Bar
IPD scale
Snellen’s near & distance chart
Illuminated bulb
Mirror PC

3. Torch
Used to see the corneal reflex, the ocular movement, the abnormality of ocular surface

4. Retinoscope
It is a hand-held instrument that is used to objectively determine the refractive power of the eye
It has a light source & a way to shine light into patients eye & observe its reflection from patients retina

5. Trial Set Trial lenses Pinhole Occluder Stenopaic Slit
Red & Green glass
Maddox Rod
Prism

6. Trial lenses
Trial lenses are sets of lenses of two types sphere and cylinder.
To measure the refractive state of the eye.
Occluder
Is a opaque disc
Used to take Vision uniocularly

7. Trial Frame
Trial frame is an adjustable frame that is used with trial lenses when measuring the patients for spectacle lenses.
The pupillary distance,lens height ,cylinder axis can be set to accommodate the patients size
It consist of 4 case. Front case is for cylindrical lens, back case for high myopic lens, other for additional lens and Occluder

8. Pinhole Pinhole accessory consist
of an opaque disc with a Pinhole (PH)  
Optical function of Pinhole: Pinhole allows the passage of central rays of light. This permits the formation of clear image.
Uses of Pinhole:
If patient’s vision improves with pinhole, patient is having uncorrected refractive error.
If patient’s vision is not improving then patient may have any pathological defect or neurological defect of the eye

9. Stenopic Slit Uses of Stenopic Slit
The Stenopaic slit consists of a rectangular aperture ranging from 0.5mm to 1.0mm in width and up to 15mm in length.
Stenopaic slit reduce the size of blur circle in the meridian at right angle to the slit, yet allows blur circle size to be unchanged in the meridian coincident with it
Uses of Stenopic Slit
To find out astigmatic power and axis.
To measure vertex distance.

10. Red & Green glass
Red and green lenses are primarily use before an eye to interrupt fusion in the assessment of binocularity. These are used for worth four dot test, FRIEND test and stereopsis.

11. Maddox Rod
Maddox rod consists of a series of powerful convex cylindrical lenses, mounted side by side in a trial lens. The glass of Maddox rod is tinted red

12. Uses of Maddox Rod
Maddox rod is used in the diagnosis of extra ocular muscle imbalance.
 Maddox rod is placed in front of right eye.
 A distance white spot light source viewed through both eye
 Right eyes see red line at 900 to the axis of Maddox rod, left eyes sees spotlight.
 Two eyes sees dissimilar images and dissociated, allowing any muscle imbalance to become manifest.

13. Prism
Prism is a triangular geometrical figure having two refracting surface meeting at an apex joined by a base
Used in treatment of diplopia and to overcome the residual deviation in squint.
In trial set, Prisms are ranging from 1/2prism diopter to 12prism diopter

14. JCC A sphero-cylinder lens
The power of the cylinder is twice the power of the sphere and of the opposite sign.
Used to refine power and axis of cylindrical power

15. Snellen's Chart Used to assess Vision. Can be used at 3mtr & 6mtr.
Also used for near vision assessment

16. Autorefractometer
Autorefractometer is an optical instrument that can automatically determine the refractive measurement of the eye.
It has a chin rest, forehead rest, viewing screen for the observer to monitor fixation.

17. Prism Bar
Prism bar are sets of plastic prisms that are attached to each other in ascending order of power.
Prism bar can be horizontal and vertical
Used to measure the vertical and horizontal amplitude of fusion of patients

18. RAF Ruler Royal Air force Ruler
Used to measure the amplitude of accommodation, near and far point of accommodation, near point of convergence

19. IPD Scale & Pupillometer
Used to measure the Inter Pupillary Distance uniocularly and binocularly

20. Other accessories
Illuminated bulb: it is kept just above and behind the patient’s head to provide the illumination for near vision assessment
Mirror: it is used for maintaining the 6m distance placed at 3m
PC: A palmtop computer. to provide the printed prescription of glasses and to collect the data of glass prescription prescribed per day

21. THANK YOU