• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.403-404
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• 2007

Compound eyes in nature present intriguing topics in physiological optics due to their unique optical scheme for imaging. For example, a bee's eye has thousands of integrated photonic units called ommatidia spherically arranged along a curvilinear surface so that each unit points in a different direction. The omni-directionally arranged ommatidium collects incident light with a narrow range of angular acceptance and independently contributes to the capability of wide field-of-view (FOV) detection. Artificial implementation of compound eyes has attracted a great deal of research interest because the wide FOV exhibits a huge potential for medical, industrial, and military applications. So far, imaging with a FOV over $90^{\circ}$ has been achieved only with fisheye lenses which rely on bulky and expensive multiple lenses and require stringent alignment. In this talk, we will discuss about the spherical 3D arrangement of the photonic structures of biologically inspired artificial compound eyes in a small form-factor to have and the functional and anatomical similiarity with natural compound eyes.

• Journal of Photoscience
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• 제9권2호
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• pp.13-16
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• 2002

A comparison of the functional components underlying photoperiodism and circadian rhythmicity in the same species is an interesting issue in the context of unravelling clock mechanisms. In the present study, covering or surgical removal of the compound eyes was performed to localize photoreceptors for photoperiodism to control reproductive diapause and for entrainment of circadian locomotor rhythms in the blow fly Protophormia terraenovae. Intact flies showed a long-day photoperiodic response. When the compound eyes were covered by silver paint, diapause incidence increased under diapause-averting conditions of a long-day photoperiod and constant light, as if flies were kept under constant darkness. Covering of a medial region of the head capsule or solvent painting of the compound eyes gave no significant effects. When the compound eyes were removed, flies did not distinguish the photoperiod, whereas removal of antennal lobes or ocelli did not affect the photoperiodism. Intact flies showed a freerunning rhythm under constant darkness. The rhythm entrained to light-dark (LD) cycles with light of high and low intensity. When the compound eyes and ocelli were surgically removed, the rhythm entrained to LD cycles with light of high intensity but freeran under LD cycles with light of low intensity. The results suggest the retinal pathways are involved in photoperiodism and that flies use both retinal and extraretinal pathways for rhythm entrainment. Under dim light-LD cycles, the retinal pathways mainly mediate rhythm entrainment. Retinal photoreceptors seem to be used both for photoperiodism and entrainment of the rhythm.

• Current Optics and Photonics
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• 제5권6호
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• pp.699-710
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• 2021

In this study, we propose a biomimetic optical structure design methodology for investigating micro-optical mechanisms associated with the compound eyes of insects. With these compound eyes, insects can respond fast while maintaining a wide field of view. Also, considerable research attention has been focused on the insect compound eyes to utilize these benefits. However, their nano micro-structures are complex and challenging to demonstrate in real applications. An effectively integrated design methodology is required considering the manufacturing difficulty. We show that photorealistic ray-traced visualization is an effective method for designing the biomimetic of a micro-compound eye of an insect. We analyze the image formation mechanism and create a three-dimensional computer-aided design model. Then, a ray-trace visualization is applied to observe the optical image formation. Finally, the segmented images are stitched together to generate an image with a wide-angle; the image is assessed for quality. The high structural similarity index (SSIM) value (approximately 0.84 to 0.89) of the stitched image proves that the proposed MATLAB-based image stitching algorithm performs effectively and comparably to the commercial software. The results may be employed for the understanding, researching, and design of advanced optical systems based on biological eyes and for other industrial applications.

• 한국응용곤충학회지
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• 제34권4호
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• pp.334-343
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• 1995

명상태와 암상태에서 벼멸구의 겹눈의 미세구조가 변화하는 것을 관찰하였다. 벼멸구의 겹눈을 암조건 혹은 광조건 하에서 최고 72시간 까지 유지하였을 경우에 비슷한 수준에서 겹눈을 절단하여 해부 현미경으로 관찰한 결고, 구조적인 면에서 서로 다른 모양을 관찰하였다. 한편, 전자현미경을 이용하여 암조건과 광조건 하에서의 겹눈의 미세구조를 비교한 결과, 단애층(palisade layer)의 넓이는 광조건하에서 암조건에서 보다 더 좁은 것을 알 수 있었다. 색소체는 암적응 상태의 눈에서는 단애층 주위에 원을 형성하고 있었지만, 감간채 주위에 밀집되어 있지는 않았다. 암적용과 광적용 상태의 눈에 있는 망막세포 내에서의 미세융모 지름은 차이가 없었으며, 수정체와 감간체의 접합 부위에 있는 색소체의 이동은 감간체의 위부분에 있은 수정체의 끝부분에서 변화가 있음을 관찰 할 수 있었다.

• Journal of Yeungnam Medical Science
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• 제17권1호
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• pp.55-65
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• 2000

VISX 엑시머레이저 굴절교정각막절제술의 경우 근시는 다영역 단연마법(Multi-zone, Single pass Ablation)으로, 근시성난시는 타원형 방식(Elliptical mode)에 의해 교정하는 원리를 채택하고 있다. VISX 20/20B $VisionKey^{TM}$ 엑시머레이저의 version 4.01 software를 이용하여 시술한 근시교정술(PRK)과 근시성난시교정술(PARK)의 임상성적에 차이가 있는지 알아보고자 하였다. 1995년 3월부터 1996년 12월까지 엑시머레이저 굴절교정각막절제술을 시행하고 술후 1년까지 경과관찰이 가능했던 PRK 152안, PARK 203안을 대상으로 후향적 연구를 시행하였다. 나안시력, 교정시력, 굴절력, 안압, 각막 혼탁, 각막지형도 등을 술후 1, 3, 6 및 12개월에 검사하였으며, 모든 환자는 12개월 이상 경과 관찰하였다. 술후 1년에 나안시력이 0.7 이상인 경우가 -7D 미만의 PRK군(110안)에서 94.8%, PARK군(104안)에서 88.1%이었고, -7D 이상의 PRK군(31안)에서 86.1%, PARK군(57안)에서 67.1%이었다. 예측도가 ${\pm}1D$ 이내인 경우가 PRK 및 PARK에 따라 -7D 미만에서 97.4%, 93,2%이었고, -7D이상에서는 각각 80.6%, 70.6%이었다. 본 연구에서 종전의 보고된 연구 결과들에 비해 나안시력 개선 및 예측도 등에서 상대적으로 우수한 성적을 나타내었음을 알 수 있었다. 대부분의 근시와 근시성난시는 VISX 20/20B $VisionKey^{TM}$ 엑시머레이저를 이용하여 효과적으로 치료할 수 있었고 PARK에서도 PRK와 유사한 정도의 우수한 성적을 얻었으나, PRK에 비해 보다 정확한 중심잡기와 축정렬 등의 중의가 요망된다. 향후 멕시머레이저와 소프트웨어의 발전에 의해 두 군 모두에서 성적향상을 기대할 수 있으리라 생각된다.

• 한국전자현미경학회:학술대회논문집
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• 한국현미경학회 1996년도 제27회 춘계학술대회
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• pp.82-84
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• 1996

• 한국양봉학회지
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• 제34권2호
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• pp.107-115
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• 2019

Bumblebees have apposition compound eyes (one on either side of the head) of about 6,000 ommatidia and three small single-lens ocelli on the frons of their head capsule. The surface of the eye is smooth and interommatidial hairs, as in the honeybee, are not developed. Each ommatidium (approx. 26 ㎛ in diameter) is capped by a hexagonal facet and contains in its centre a 3 ㎛ wide, columnar light-perceiving structure known as the rhabdom. Rhabdoms consist of thousands of regularly aligned, fingerlike microvilli, which in their membranes contain the photopigment molecules. Axons from each ommatidium transmit the information of their photic environment to the visual centres of the brain, where behavioural reactions may be initiated. Since bumblebee eyes possess three classes of spectrally different sensitivity peaks in a ratio of 1:1:6 (UV= 353 nm, blue= 430 nm and green=548 nm) per ommatidium, they use colour vision to find and select flower types that yield pollen and nectar. Ommatidial acceptance angles of at least 3° are used by the bumblebees to discriminate between different flower shapes and sizes, but their ability to detect polarized light appears to be used only for navigational purposes. A flicker fusion frequency of around 110Hz helps the fast flying bumblebee to avoid obstacles. The small ocelli are strongly sensitive to ultraviolet radiation and green wavelengths and appear to act as sensors for light levels akin to a photometer. Unlike the bumblebee's compound eyes, the ocelli would, however, be incapable of forming a useful image.

• 대한약침학회지
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• 제4권2호
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• pp.35-47
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• 2001

Objectives : Through the literatures on the effets of Bufonis Venenum, we are finding out the clinical possibility and revealing the more effective to intractable diseases. Methods : We investigated the literatures of Oriental Medicine and experimental reports about Bufonis Venenum. Results : 1. Bufonis Venenum is made of bufonidae bufo bufo gargarizans cantor or bufo melanostictus schneider of white serum which secreted from parotid gland or dermato gland, and it is dried for using. 2. In oriental medicine, Bufonis Venenum has been mainly used on the tumors, cacanthrax and dermatic disease, and then it has been clinically used on infantile athrepsia, tetanus, sore throat, toothache, and so on. 3. The pharmacological effects of Bufonis Venenum are cardiotonic, respiration stimulation, depressor or vasopressor, topical anesthcsia, hallucination, striped muscle stimulation, antiasthmatic, antibacterial, antiinflammatory, anticancer, diuretic, immuno effects, etc. 4. Bufonis Venenum is largely divided in ether binding steroid compound, hydroxyl steroid compound, carboxyl or aldehyde steroid compound, indole compound, and adrenaline, cholesterole, etc. 5. Symptoms of Bufonis Venenum poisoning in digestive system are vommitig, abdominal pain, diarrhea, dehydration, in circulatory system are palpitation, shock, bradycardia, in nervous system are vertigo, somnolentia, muscle-tendon reflex weakness, and critical conditions to tissue necrosis and heart attack. 6. Ways to treat Bufonis Venenum poisoning include gastric irrigation with $0.2~0.5\%$ potassium permanganate fluid and atropine $0.5{\sim}1.0mg$ subcutaneous injection. From the chinese book of Bon Cho Gang Moke(本草綱目), if white serum of Bufonis Venenum enter the eyes, it happens the edema and pain. And then washed the eyes by juice of Lithospermi Radix(紫草) that the edema is removed. Conclusions and Discussion : The results from above literary studies show that prescriptions and Aqua-acupuncture of Bufonis Venenum could be clinically used to sedative, anticonvulsant, antibacterial, antiinflammatory, anticancer and topical ataralgesia. However it is expected that pharmacological and side effects of Bufonis Venenum are further studied.

• Applied Microscopy
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• 제1권1호
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• pp.27-34
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• 1969

The compound eyes of the adult Drosophila melanogaster were. fixed in 1.25 per cent glutaraldehyde and 1 per cent osmium tetroxide buffered with sodium cacodylate at pH 7.2. Double fixed specimens were dehydrated using the alcohol series and embedded in Epon 812. They were sectioned with porter blum and JUM 5B ultra-microtome and then stained with lead hydrooxide and uranyl acetate. All thin sections were examined with Hitachi HS-7 or HU-11 electron microscope. The rhabdomere of the compound eye is composed of numerous microvilli packed, arranged, and projected from inner edge of each retinal cell. Each microvillus consisted of a centrum, about $82{\AA}$ in diameter, surrounded by the substances, about $105{\AA}$ in width, which were bounded with double membrane about $44{\AA}$ in thickness. In each inner edge of the microvilli, there was a cylinder, about $175{\AA}$ in diameter, in parallel with retinal cells, which contained a cylindrical axis about $583{\AA}$ in diameter. The surface of the outer edges .of .the microvilli was bounded with reticullar substances about $500{\AA}$ in thickness.

• 한국안광학회지
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• 제7권2호
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• pp.67-71
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• 2002

본 연구는 전북지역 고등학생 비정시 182명 364안을 대상으로 타각적, 자각적 시력 검사를 시행하여 비정시의 정도 및 굴절 이상상태를 연구하였다. 1. 눈의 형태는 근시는 85.7%, 원시는 7.6%, 그리고 정시는 6.6%로 나타났다. 2. 굴절이상안은 단순근시 29.6%, 근시성 복난시 56.3%, 근시성단난시 7.2%, 원시성단난시 1.8%, 원시성 복난시 1.2%, 혼합난시 1.8%, 단순원시 1.8% 이었다. 3. 난시의 축은 직난시 78.7%, 도난시 13.9%, 사난시 7.4%이었다. 4. 난시의 굴절력은 0.50dptr에서 1.0dptr가 64.6%. 1.0dptr 에서 2.0dptr가 29.1%, 2.0dptr 이상이 6%이었다. 5. 근시성 굴절이상안의 등가구면굴절력은 -0.50dptr 에서 -2.0dptr 이하 40.1%, -2.0dptr에서 -6.00dptr 이하 56.6%, -6.00 이상이 36.8% 이였다. 6. 원시성 굴절이상안의 등가구면굴절력은 2.00dptr 이하 50%, 2.00dptr 이상이 50%이었다.