The Main Features Of Optometry Equipment

Reflective instrument is an electronic objective optometry equipment, is the combination of refractive technology and electronic computer technology products. There is no need for the subjective judgment of the clinician and the subject, and the refractive parameters are evaluated objectively by the pre-set criteria. As the computer optometry simple, fast, short learning cycle, suitable for rapid access to objective diopter and as the main inspiration of the starting point or for daily eye care screening. With the application of high-tech optometry equipment, the accuracy of optometry equipment has been greatly improved, many instruments integrate corneal curvature or corneal topography function, and some manufacturers of instruments and integrated refractometer automatically online, Optometry Instruments The results directly into the integrated refractometer, easy to use; portable optometry equipment can also be used in the surgical process and screening.

Most optometry instruments are based on the principle of indirect ophthalmic lens, the use of two objective lens or focusing mirror and a beam splitter, the light source directly from the pupil edge into the detection of the cursor can move along the projection system, located in the front focal plane projection Lens, Optometry Instruments the image will be at infinity, then in the eyes of the retina on the clear focus; if the eye is eye refractive error, detection of the cursor before and after the move, making it focused on the retina, most of the optometry instrument is to change The light spreads into the eye to make the cursor clearly imaged on the retina and automatically calculate the eye's refraction.

Modern optometry instrument design usually has two main features:

1. Regulatory control For most optometry methods, regulatory control is particularly important. Almost all of the refractors require the subject to watch the test cursor or cursor image, Optometry Instruments the results stimulate the adjustment and make the results of myopia correction or hyperopia correction, although the test cursor through the optical design at infinity, because the instrument is very close to being seized Of the face, it induced the near-perceived regulation, so in the design process, the test cursor "fog visual", before the start of the test, Optometry Instruments the seizure first saw a "fog" cursor, in order to relax But can not completely remove the near-perceived regulation.

2. Detection of light for the infrared light currently used in the detection of optical instruments are used to detect the wavelength of 800 ~ 950 nm infrared light. The reasons are: ① infrared absorption by the intraocular tissue is less visible light, the reflection of the light through the fundus more. Therefore, the detection of light through the intraocular vector after the loss of light energy less, especially the measurement of refractive media opacity of the eyes is more important. ② for the eye, the detection of visual and detection of light is not visible, Optometry Instruments better overcome the measurement caused by the adjustment of the problem.

Due to the different production companies, optometry instrument design and structure are also different, the inspectors in the use of optometry equipment before the need to read the instructions in detail. The common structure of the optometry instrument is: ① the cursors watched by the examiner. ② can adjust the jaw and head by, so that the patient's head during the inspection fixed. ③ joystick can be before and after, up and down, left and right movement to adjust and adjust the location of the subject's eyes. ④ monitor shows the location of the eye and the measurement results. ⑤ printing device.

Optometry steps

Prepare for

(1) disinfection jaw and head against.

(2) require the subject to remove their glasses or contact lenses.

(3) Turn on the power switch.

(4) Initialize the instrument parameters, including the parameters of the cylinder, the vertex distance, the contact lens, the display parameters of the monitor, the subjective or objective mode, Optometry Instruments the choice of the target, the printing mode and the display mode of operation.

(5) Adjust the height of the chair and the height of the instrument so that the position of the subject and the inspector is comfortable.

(6) Loosen the lock switch.

(7) to guide the seizure of the chin into the jaw, forehead by the head to rely on; told the measurement process to keep the head fixed.

(8) lift the jaw until the subject's outer canthus angle is aligned with the height sign on the stent.

2. Check the steps

(1) Select the measured items, usually including diopter, corneal curvature. Optometry Instruments It should be noted that different manufacturers and different types of instrument functions may be different.

(2) to guide the subjects to look at the front of the refractometer inside the cursor.

(3) through the instrument monitor to observe the location of the right eye, and use the joystick before and after focusing to make the image clear; up and down the left and right to move the joystick to the cornea point cursor in the center of the pupil.

(4) Press the button on the joystick to measure the diopter or corneal curvature. If the automatic mode is selected, the focus is centered and the instrument is automatically measured three times.

(5) repeated measurements more than three times.

(6) Repeat steps (3) to (5) to measure left eye refraction or corneal curvature.

(7) If the corneal diameter is measured, after step (3) is completed, the corneal nasal and temporal border is selected by the control button. Press the button on the joystick to measure the corneal diameter.

(8) to print or record the measurement results; usually the instrument automatically select the two closest to the higher reliability and the value as the final result.