Eye diseases are closely related to each of us, and many people are sensitive to any discomfort in the eye and are often the first to seek medical attention. This is because it is widely believed that the quality of life is directly related to the quality of visual function. However, ophthalmology is a very specialized clinical department, not to mention ordinary patients, even doctors in other departments of the hospital for ophthalmology knowledge, but also often very superficial. With the improvement of medical diagnosis and treatment, there are many new equipment and techniques in ophthalmology, so it is necessary to make a brief explanation. Outpatient common tests and their significance: Visual acuity test: This is one of the most basic tests for ophthalmology examination. It can give the doctor an accurate visual impression of the patient’s condition in the first place. All patients associated with visual quality abnormalities should first receive a binocular vision examination. It is also often recommended for patients who have a dry eye due to a swollen eyelid that has little to do with vision. Slit lamp examination: The slit lamp is a microscope that examines the external eye, the anterior segment of the eye, and the anterior vitreous. Combined with a number of contact and non-contact optical components, it allows for examination of the fundus of the eye. The slit lamp is one of the most commonly used devices by ophthalmologists and is a test that essentially all ophthalmic patients undergo. Fundus examination: There are many different ways to examine the fundus, ranging from examination under the slit lamp to specialized direct or indirect fundoscopy. The purpose of a fundus exam is to look for the presence of fundus disease or to rule out the presence of fundus disease. Fundus examinations are required for most patients with visual impairment. Regular routine fundus examinations for children, adults, etc. are also considered necessary. There are two types of fundus exams: under normal pupils and under dilated pupils. Doctors prefer to perform the latter type of exam because it is clearer and more extensive, so patients should also have their pupils dilated if there are known lesions in the fundus or if a detailed fundus examination is needed. Optometry and trial lenses: Optometry is an examination of the refractive state of the eye using different methods, currently mainly computerized optometry. The purpose of optometry is to understand the patient’s current refractive state, such as myopia or hyperopia. The trial is not the same as a prescription, but rather a test to give the patient the best corrected visual acuity based on the results of the optometry. The trial is an important piece of information for the clinician to know the best corrected visual acuity for the patient. Intraocular pressure check: There are more ways to check the intraocular pressure, there are contact and non-contact, currently commonly used is the gas non-contact way, that is, fast and safe, the patient’s cornea is in good condition can receive this test. Some patients with high intraocular pressure or poor corneal condition may require contact IOP testing. In addition, the use of acupressure is a convenient and important method of estimating IOP in certain situations, based on the experience of the physician. All patients with suspected glaucoma or a possible glaucoma attack should have an IOP check, and routine eye exams should also be performed if possible. IOP testing is inexpensive, convenient and safe, and the presence of abnormalities usually means that there may be a greater risk of disease, so this test can be expanded appropriately. Tear duct irrigation: Many patients mistakenly believe that tear duct irrigation is a treatment, but in fact, tear duct irrigation is basically no treatment for tear duct obstruction. For infectious lacrimal disease, antibiotics are usually added to the irrigation solution. Tear duct irrigation is diagnostic for patients with lacrimation and is often a mandatory part of the examination for patients preparing for internal eye surgery such as cataracts. Optical Coherence Tomography (OCT): Unlike regular CT exams, OCT exams are not performed using X-rays. OCT exams are safe, non-radioactive and non-invasive, and are an important tool for detailed examination of the retina, especially the macula and optic disc, and are one of the common exams used by fundoptologists. Because OCT is non-invasive and safe, it has also become one of the main tests used by many patients with fundus disease to track changes in their condition at follow-up appointments. Fundus photography: Although there is no substitute for a physician to examine a patient’s fundus. However, fundus photography using advanced fundus cameras is important for disease observation, documentation, follow-up, and research. Unlike the subjective description of a physician, fundus photography is objective. Many fundus diseases are variable in nature, so it is necessary to receive fundus photography at different times of disease onset. Ultrasound biomicroscopy (UBM): It is a type of ultrasound examination of the anterior segment of the eye that provides a good exploration of the structures in the patient’s anterior segment. It is important for glaucoma, congenital malformations of the anterior segment of the eye, ocular trauma, and preoperative examination for internal eye surgery. Ultrasound of the eye: Ultrasound examinations are usually non-invasive and painless. Ocular ultrasonography is important for patients with superficial ocular tissue masses, orbital disease, and refractive interstitial confusion. Electrophysiological examination of the eye: electrooculography, electroretinography, and visual evoked potential examination are all electrophysiological examinations of the eye, which are relatively complex and time-consuming. These examinations are generally required for patients who cannot speak well about their vision, such as children and patients with intellectual disabilities, patients with extensive lesions of the retinal pigment epithelium and optic cells, and patients with refractive interstitial clouding. Visual field examination: Visual field examination requires the cooperation of the patient. It is important for the diagnosis and follow-up of glaucoma. It is also important in the field of neuro-ophthalmology, where specific types of visual field abnormalities can indicate the presence of central nervous system disorders. Visual field examinations are also indicated in diseases such as retinitis pigmentosa. Fundus angiography: Fundus angiography, performed after intravenous injection using a contrast medium, is an invasive test but is important for the diagnosis of retinal diseases, especially retinal vascular diseases. Sometimes, fundus angiography plays a decisive role in the diagnosis of the disease and may lead to a different direction of diagnosis and treatment. Fundus angiography is one of the common tests used by ophthalmologists. With the improvement of the production process of contrast agents, fundus angiography is much safer and usually acceptable unless there is severe liver or kidney insufficiency, cardiac insufficiency or allergy. In addition, corneal confocal microscopy, OCT of the anterior segment, corneal fluorescence staining, corneal topography, ocular CT/MR, glaucoma provocation test, and proptosis examination are often used in the examination of corneal refractive surgery, glaucoma, and orbital disease. Laboratory tests such as serology, chromosomal and genetic testing are also frequently performed in specific diseases.