General Information

Serial #

N/A

Part Number

17

Total Parts

20

AKA

N/A

Patents

N/A

General Description

METAL/ SYNTHETIC

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

21.0 cm

Width

13.0 cm

Height

12.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Medical Technology

Category

Medical equipment

Sub-Category

N/A

Manufacturer

AKA

KEYSTONE

Country

United States of America

State/Province

Pennsylvania

City

Meadville

Context

Country

Canada

State/Province

Ontario

Period

THIS TYPE OF VISUAL TEST INSTRUMENT USED C. 1950S+

Canada

INSTRUMENT OWNED, AND PRESUMABLY USED, BY CANADIAN BUSINESS SUPPLY CO. R.L. CRAIN LTD. (1894 TO PRESENT)

Function

TO EVALUATE THE VISUAL ACUITY (INCLUDING DEPTH AND COLOUR PERCEPTION, AND PERIPHERAL VISION) OF EMPLOYEES.

Technical

EXAMPLE OF VISUAL TESTING INSTRUMENT OF TYPE USED IN WORKPLACE TO SCREEN EMPLOYEES FOR VISION PROBLEMS. TESTING FOR VISUAL ACUITY, DEPTH AND COLOUR PERCEPTION, PERIPHERAL VISION, ETC. COULD BE ADMINISTERED SIMPLY AND RAPIDLY BY AN OPERATOR REQUIRING ONLY MINIMAL TRAINING. ONCE IDENTIFIED, EMPLOYEES WITH VISION PROBLEMS COULD BE DIRECTED TO A SPECIALIST, IF NECESSARY. (REF. 1)

Area Notes

Unknown

Details

Markings

"KEYSTONE/ PERIOMETER/ PATENT APPLIED FOR/ MADE IN U.S.A. BY/ KEYSTONE VIEW CO./ FOUNDED 1892 MEADVILLE, PA." printed on mfr's plate. "KEYSTONE VIEW CO./ MEADVILLE, PA. U.S.A./ Patent No. 2604811" printed on scale face. Scale divided 105 to 0 to 105, in graduations of 5.

Missing

N/A

Finish

Unknown

Decoration

N/A